ALBERT

Notes: The Ordnance Survey makes extensive use of air survey in its mapping programmes at scales of 1 : 1250, 1 : 2500 and 1 : 10 000. A short history of the development of air survey within the Ordnance Survey leads into a description of current methods including the flying, processing and aerial triangulation tasks as well as the plotting of the maps by instrumental or graphical means.

Notes: A number of proposals have been put forward for the extraction of three dimensional data from a pair of electron microscope photographs taken from different angles. The methods used have, in general, been either point by point analyses or rather inconvenient. This paper shows that an existing photogrammetric plotter of topographic accuracy can, with very simple modification, be converted to give continuous plotting facilities from certain such micrographs.

Notes: The author reminisces upon a career of almost 40 years as a practising surveyor photogrammetrist, both as a Royal Engineer officer and as a director of a commercial survey organisation. The reminiscences include service with the Survey of India, war time operations in the Middle East and South East Asia Command, and commercial surveys of all types in developing countries. Professional service with international surveying and photogrammetric organisations is also mentioned, with particular reference to the fraternal aspects of international photogrammetry.

Notes: An increasing number of applications of photogrammetry are concerned with the analysis of models, constructed to simulate proposed or existing conditions in architecture and engineering. The paper draws attention to some of these projects and reports one example in detail.

Notes: The author describes the photogrammetric equipment in use by the Royal Commission on Historical Monuments (England), the methods used and the work that is being done in architectural recording. The difficulties and the possibilities of future architectural work in the United Kingdom are discussed and the achievements of some other countries in this field are reviewed.

Notes: The article discusses a general classification system applicable to digital ground models (D.G.M.) as used in highway design. Examples of the various categories are given, together with details of some advantages and disadvantages. The place of the D.G.M. in the highway design system is described in conjunction with traditional methods. The relationship between accuracy, density and economy of D.G.M. systems is examined. Finally an experiment is described which investigates the accuracy of various D.G.M. systems; it is being conducted by the Transport and Road Research Laboratory.

Notes: Book reviews in this article:OPTIMIZATION TECHNIQUES IN LENS DESIGN. By T. H. Jamieson.ADJUSTMENT BY LEAST SQUARES IN GEODESY AND PHOTOGRAM-METRY. By R. A. Hirvonen.AERIAL PHOTO-ECOLOGY. By J. A. Howard.PROCEEDINGS OF THE ISP COMMISSION IV SYMPOSIUM 1970. Editor J. Kure.

Notes: The use of aerial photography for hydrographic requirements is discussed, with particular reference to current circulation in an all water area. The paper examines the criteria and limitations imposed by an environment which is alien to normal topographic photogrammetry.

Notes: SYNOPSIS. When two strains cf T. pyriformis that do not require exogenous pyridoxine are crossed, all progeny grow without the vitamin. Offspring from crosses of two pyridoxine requiring clones require pyridoxine with the exception of a few which will grow without pyridoxine. The ratio is approximately 3:1 favoring the pyridoxine requiring category. In matings involving the homozygous dominant pyridoxine requiring clones with the double recessive mutant, that is +/+ X p/p, all of the resulting progeny need pyridoxine. Test crossing these heterozygotes (+/p) with the parental pyridoxine non-requiring clones (p/p) gives offspring approximating a 1:1 ratio. Matings between two heterozygotes derived from breeding experiments also yield progeny in approximately 3 pyridoxine requiring: 1 pyridoxine non-requiring. All data indicate selection for the heterozygote in the population and a possible selection against either homozygote. The great abundance of heterozygotes and rarity of recessive homozygotes in natural habitats corroborates these findings. The genetic evidence supports a single gene hypothesis although the possibility of multiple closely linked genes cannot be ignored. There is also the possibility that a dominant suppressor gene may function in blocking the activity of the pyridoxine mutant genes. Moreover, if this gene exists it may be incompletely dominant since the heterozygote grows slightly on deficient media.

Notes: SYNOPSIS. Trichodina urinicola was found in newts, Triturus cristatus and T. taeniatus, in three localities in Czechoslovakia. The ciliate populations showed important differences on the basis of which they were separated as three new forms of this species: T. urinicola f. typica, T. urinicola f. bohemica, both from Triturus cristatus, and T. urinicola f. taeniatus from Triturus taeniatus. The great variability of trichodinids is evident from the literature as well as from our own observations, so that these new forms are to be regarded as provisional ones until it is possible to decide on the basis of a large number of observations the extent of specificity and variation of individual endozoic species of Trichodina. A detailed description of these forms is given as well as a comparison with the known species of trichodinids inhabiting the urinary tract of amphibians. A brief comment on the present taxonomy of the Urceolaridae in general is outlined.The need for a uniform description of these ciliates is emphasized; in connection with this, the taxonomic value of individual body characters is discussed. Special attention is paid to the adhesive disk of Trichodina, the structure of which is of greatest importance in the taxonomy of this group. On the basis of Dogel's and Fauré-Fremiet's descriptive methods employed in study of trichodinids, a proposal of a uniform description of Trichodina is made which involves all the important features of these protozoa.

Notes: SYNOPSIS. Several substrains of Euglena gracilis var. bacillaris made chlorotic by treatment with pyribenzamine or streptomycin, or by growth at high temperature (35–36°C.), have been examined for their carotenoid content. They differ from the normal green strain both qualitatively and quantitatively. Some strains produce no detectable carotenoids while the carotenoid concentration in the strains producing most is at best only one-fifth that of the normal strain. In all substrains producing carotenoids, the carotene fraction consists of β-carotene accompanied by some members of the phytofluene series. In only two of these substrains, HB-G and PBZ-G3, are xanthophylls produced in significant amounts. In HB-G, the main pigment is echinenone, and in PBZ-G3 it is zeaxanthin. The significance of these findings is briefly discussed.

Notes: SYNOPSIS. Association of gamonts of Pyxinia crystalligera takes place in the midgut of its beetle host, Dermestes vulpinus. At 25°C. the development of gametocysts to the point of liberation of sporocysts is completed between about 15 hours and 27 hours after the gametocysts are deposited with fecal material. Dehiscence is favored by relative humidities of 0% to 90%, but is not favored by a relative humidity of 100%. During the early development of the gametocysts outside the host, the crystals and paraglycogen granules in the cytoplasm of the associated gamonts become concentrated in large masses. The gametes are formed at the periphery of the gamonts. After fusion of the gametes takes place and the sporoblasts begin to develop, the residual cytoplasm containing the inclusions moves outward to form a continuous layer next to the gametocyst envelope, so that the sporoblasts become crowded into a central core. A few hours before dehiscence is initiated a clear area appears on the upper side of the gametocyst. The contents of the gametocyst begin to shrink away from the envelope except in the region of the clear area. Eventually the sporocysts emerge through the clear area and press against the envelope of the gametocyst, causing formation of a conical papilla in the envelope. With continued pressure from the sporocysts, the papilla ruptures at its tip, and the sporocysts emerge in a continuous thread until dehiscence is completed. The thread of sporocysts may attain a length of about 11 mm.

Notes: SYNOPSIS. The steps leading to purine ring closure were examined in Strigomonas oncopelti. The flagellate has an obligate adenine requirement (hypoxanthine and guanine are inert) when grown without p-aminobenzoic acid. The imidazole counterpart of adenine but not the imidazole counterpart of hypoxanthine was active. A pathway for purine biosynthesis compatible with these results is sketched.

Notes: SYNOPSIS. The Nuttallia of the gerbil is transmitted by Rhipicephalus secundus only if the infected meal is taken by the larva, and the subsequent nymphal stage is the only one which is able to infect. There is no transovarial transmission.Infective trophozoites remain in the larval caeca for about 12 hours after gorging. The infective nymph is able to give rise to new infections at various times after it has been allowed to feed, but never later than the third day after disengagement from the host.

Notes: SYNOPSIS. The process of autogamy in unassociated individuals of Paramecium polycaryum was reported by the author in 1954. In May, 1955, conjugation was first seen in this species in cultures collected by me at Annamalainagar, South India, thus removing it from the list of non-conjugating species. This appears to be the first instance in which the process of autogamy was detected prior to observation of conjugation in the same species. Autogamy occurs in singles of the Indian race and appears to be similar, cytologically, to that of American races. The details of the micronuclear behavior in conjugation parallel those of autogamy in singles. In fact, the conjugation process seems to be one of double autogamy (cytogamy), rather than of reciprocal gametic interchange. Paroral cones, often of fair size, are formed but breakdown of the cones to permit micronuclear passage has not been observed. In conjugation there are the usual three pregamic divisions; the first shows four characteristic crescents. The resulting nuclei may all participate in the second division. Fertilization occurs in the paroral cone area. Frequently, separation of the conjugants takes place immediately after the first division of the synkaryon. The old macronucleus undergoes very little change prior to the last postzygotic micronuclear division in the ex-conjugant, when it goes into a skein condition. Four macronuclear and four micronuclear anlagen are formed in the ex-conjugants at the completion of reorganization. On occasion giant individuals of P. polycaryum were observed to have ingested numbers of Tetrahymena pyriformis. The presence of an unidentified rod-like organism in the cytoplasm of the paramecia (non-conjugating) was detected in one collection from Bangalore, India.

Notes: SYNOPSIS. The effects of some environmental influences on the cycle of Trypanosoma diemyctyli in Triturus v. viridescens are described. Bleeding of the host produced a reduction in the number of trypanosomes but did not affect their growth rate. The temperature at which the host was maintained affected the cycle of the trypanosomes. The length of the post-inoculation latent stage increased from 24 hours at 25°C. to an indefinitely long time at 5°C. The trypanosomes were found to be dimorphic. Adult parasites of the short form had a range of 45–75 μ and those of the long form of 76–116 μ. Growth rate of the trypanosomes was inhibited or greatly retarded at temperatures of 10°C. or lower and was greatest at 25°C. The size attained by the parasites and the number of parasites were greatest at 15°C. At this temperature the infection was pathogenic and the dimorphic parasites were in their long form. At the higher temperatures (20–25°C.) the infection was non-pathogenic with the trypanosomes in their short form.The infection is primarily one of adult newts. Experiments indicated that the larvae were resistant to the trypanosomes at all temperatures while the red efts were not. The latter are usually free from the trypanosomes because they are not exposed to them. Attempts to infect other newts and to locate any cryptic stages by the injection of blood and tissues from infected newts gave negative results.Starvation, sodium salicylate, and treatments used to control fungus infection of the newts had no detectable effects on the trypanosomes.

Notes: SYNOPSIS. A comparative study of five species of Tetrahymena, including thirteen strains, was made to ascertain their ability to act as facultative parasites. A variety of experimental hosts, including both vertebrates and invertebrates, were inoculated with axenic cultures of protozoa. Infections were numerous in both larval and adult insects. Tissues of living vertebrates were invaded by one species of Tetrahymena through artificially produced wounds.

Notes: SYNOPSIS. Unabsorbed, complement-inactivated antisera produced in rabbits were used in an immobilization system to study the serology of 31 strains of Tetrahymena pyriformis grown in axenic cultures at 26°C. Fourteen serological “groups” were found: 1. “H”: H, E, S, GC, L3, W, T, GHH, G1-R and sublines W-P and T-P; 2. “PR”: PR; 3. “GL”: GL; 4. “LR”: LR; 5. “L1”: L1 and L2; 6. “GP”: GP and Ch-S; 7. “WH”: WH6, WH14 and WH52; 8. “N”: N and HS; 9. “Y”: Y and TC; 10. “AA”: AA1, AA2 and AA4; 11. “F”: F and BF; 12. “Gf-J”: Gf-J; 13. “EZ”: EZ; 14. “Lava”: Lava. Not all of these “groups” were completely distinct; weak or variable cross-reactions occurring for particular cultures and antisera during the course of several years of observation suggested a relationship in terms of serotype potentialities, for strains in groups 1 and 2, and in groups 2, 3, 4, 5, and 6. Non-reciprocal cross-reactions are tentatively explained in terms of population fluctuations of serotype within particular cultures; several other suggested explanations remain possible. On the whole, however, the strains remained remarkably stable in dominant serotype.Observations on Tetrahymena in paralyzing antisera, with respect to the extrusion of a gelatinous exudate, in general confirmed previous observations by others. “Chain” formation was noted upon recovery, under conditions suggesting that the chains do not always derive entirely from incomplete cytokinesis of dividing organisms but that at least sometimes an aggregation of separate individuals is also involved. Synchronized division was observed for recovering organisms. A gelatinous material was obtained by centrifugation of a large number of individuals; this material provided a degree of protection to the organisms against antiserum effects while other colloidal materials did not, but the protective effects proved nonspecific in the sense that they were not confined to particular strain-antiserum combinations.

Notes: SYNOPSIS. A rapid quantitative method for measuring trypanostatic activity by means of the nonpathogenic flagellate Herpetomonas culicidarum is described. Of the known trypanocidal agents tested, pentamidine was the most active; stilbamidine and propamidine somewhat less active. H. culicidarum is more resistant to these agents than are some pathogenic hemoflagellates. Two new antifungal antibiotics, nystatin and heptamycin (a candicidin-like antibiotic), had powerful trypanostatic activity in vitro. The potential trypanostatic activity of antifungal agents is noted.

Notes: SYNOPSIS. Approximately fifty % of Natrix piscator from the vicinity of Bombay showed a haemogregarine in the peripheral blood. Schizogonic stages were found in great abundance in the lung capillaries, and occasionally in other internal organs. No parasites could be demonstrated in trombiculid mites of the genus Schongastia fed on infected snakes. Various developmental stages were found in the leech, Hirudinaria granulosa allowed to feed on infected Natrix piscator. The haemogregarine was originally described from this host in Ceylon on the basis of blood stages only and was named Haemogregarina mirabilis. Although the parasite exhibits several of the characters diagnostic of the schizogonic stages of the genus Hepatozoon, it is advisable for the present to retain it in the genus Haemogregarina.

Notes: SYNOPSIS. A new species of a freshwater reticulate dinoflagellate, Woloszynskia limnetica, is described. The membrane structure and the shape of the membrane plates change during cell development. The rod-shaped mitochondria found among the membrane plates disappear in the adult cells; they constitute a center from which starch grains develop. Mitochondria also occur free in the endoplasm. Different physiological activities appear to be performed by morphologically identical chondriosomes. The stigma changes in different phases of the life cycle. The physicochemical properties of the ectoplasm govern the formation of specific structures of the membrane plates, which in turn determine the taxonomic position.

Notes: SYNOPSIS. Pseudomicrothorax dubius, a rather rare protozoon assigned by Kahl to the trichostome order of ciliates, has been found and positively identified for the first time in America, and its morphology and morphogenesis have been studied in detail with the aid of modern techniques. The Chatton-Lwoff silver impregnation method is considered indispensable in acquiring an understanding of the ciliate's infraciliature: both its anatomy in the mature vegetative animal and its activities during the morphogenetics of binary fission.Stomatogenesis is of a complex type, considered here as “semi-autonomous” in nature, although a single, true stomatogenous meridian also is involved. Details of this explicit morphogenetic phenomenon are offered.The presence of a true zone of three adoral membranelles, never before recognized with any accuracy in this ciliate, a buccal cavity and associated structures, and the mode of stomatogenesis have led the writers to propose transfer of the genus Pseudomicrothorax from the Trichostomatida to the order Hymenostomatida.

Notes: SYNOPSIS. Studies of the body ciliature of Balantidium coli and B. caviae (?) after Breslau's opal-blue and Klein's silver nitrate techniques revealed a preoral-dorsal suture area where some of the ciliary rows fail to reach the peristomial margin. The incomplete kineties ranged up to a dozen in number and were variable in arrangement. In a count of 100 specimens of B. caviae (?) the incomplete kineties were at the right of the suture in 39, at the left in 24 and on both sides of the suture line in 37. At the posterior end not many kineties reach the pole but no sutural pattern was seen in that region. Scattered irregularities in the ciliary rows were sometimes seen.Studies of the oral region tend to confirm the view of Fauré-Fremiet that the peristomial ciliature consists of short rows of cilia which are continuations of the anterior body kineties. Membranelles were not found. Thus, some species of Balantidium, at least, show affinities with the Holotricha in agreement with Nie and Fauré-Fremiet.Fission commonly produces two equal-sized daughters but many cases of unequal division were observed. In both these species conjugants are much smaller than vegetative animals and two preconjugant divisions are indicated, the first of which may be unequal.During the early stages of fission, the anterior ends of the kineties of the posterior daughter change direction, becoming oblique in the fission zone. In this region the kinetosomes multiply; possibly some of the kineties also divide but evidence for this is incomplete. No evidence of reorganization at the anterior end of the anterior daughter was seen.Attempts to infect hamsters with B. coli and B. caviae (?) failed. No parasites were found in two collared peccaries repeatedly examined.

Notes: SYNOPSIS. Purification by migration on solid agar plates was studied with a small soil amoeba, Acanthamoeba sp., and a large fresh-water amoeba, Amoeba proteus. Purification seems accomplished largely by two mechanisms: egestion and attrition of contaminating organisms. Digestion may also play a role but probably is less important. The migration method is applicable to motile forms of the two amoebae which differ greatly in volume and motility. Therefore the method may be of potential value in purifying many species. Modifications which should extend the usefulness of the method are considered.

Notes: SYNOPSIS. The gametes of Trichonympha grandis fuse quite differently from those of all the other species of Trichonympha in Cryptocercus; fusion is partial and temporary instead of complete and permanent as in other species. In this species, as in the others, fusion brings about the disintegration of all the extranuclear organelles of the male gamete, but none of those of the female; these persist to become the organelles of the zygote. Gametic union accomplishes two things: loss of extranuclear organelles of male and fusion of pronuclei. Unlike that of the other species of Trichonympha, the cytoplasm of the male gamete of T. grandis contributes slightly, if at all, to the formation of the zygote.

Notes: SYNOPSIS. A new species of Hepatocystis (H. hippopotami) is described from the blood and liver of a Rhodesian hippopotamus (Hippopotamus amphibius). Its relationship with other members of the genus is briefly discussed.

Notes: SYNOPSIS. The role of eleven different types of achromatic figures in chromosomal movement of Barbulanympha is analyzed. When only one pole is present, no chromosomes are ever connected with it, and hence they do not move. The chromosomes go through their usual life cycle including pairing, but remain in the parent nucleus, which, of course, does not divide. When two poles are present with only one pole near the nucleus, the poles, which are the distal ends of the elongate centrioles, do not cooperate in the formation of a central spindle and the chromosomal behavior is just as if there were only one pole—no movement. The same is true when more than two poles are present with only one near the nucleus.Unless a central spindle is present, movement of chromosomes never occurs. However, when many central spindles are present, sister chromosomes may separate and move to poles which are not directly connected by a central spindle. In other words, sisters may separate without moving along a central spindle.In binucleate cells with one central spindle the chromosomes of one nucleus move to the poles, but those of the other do not. Movement always occurs in the nucleus that has its nuclear membrane depressed by the central spindle. When two or more central spindles are present, the chromosomes of both nuclei may move to the poles.

Notes: SYNOPSIS. Euplotes eurystomus Wrzesniowski was cultured on bacterial media with Tetrahymena pyriformis serving as the food organism. Animals were injured with various types of operations using the Chambers' micromanipulator. These animals were followed during the course of their regeneration using various nuclear stains, silver impregnation techniques and vital staining methods. It was found that two cirral fields arose as a result of injury removing one or more of the locomotor organelles and that the posterior field was soon resorbed, while the anterior one replaced all of the old cirri of the regenerating animal. In addition, in response to this sort of injury, complete nuclear reorganization took place. Animals which were injured in a manner not affecting the locomotor organelles directly, responded by proliferating a fine network in the area of injury. This network seemed to reinforce the injured area and persisted until the next binary fission of the animal. No nuclear reorganization took place in these cases.

Notes: SYNOPSIS. The leech, Erpobdella sp., is a suitable invertebrate host for Trypanosoma ambystomae. The developmental cycle involves a mononucleate, rounded body derived from the bloodstream form; this body then transforms into a large plump crithidia. Subsequent divisions yield medium crithidia, small crithidia, and ultimately, metacyclic trypanosomes.

Notes: SYNOPSIS. California ground squirrels (Citellus beecheyi) were found to be infected with trypa-nosomes whose most striking morphological features are an unusually large kinetoplast and a long, tapering posterior end. The total length is 25.2 μ, and body length is 18.0 μ. This “lewisi”-type species is compared with other trypanosomes reported from American ground squirrels, but a specific diagnosis is not made because the life cycle has not been observed and because morphological features of trypanosomes are known to vary widely under differing environmental conditions.

Notes: SYNOPSIS. The basal apparatus of the flagella and kinetoplast in Leishmania donovani have been studied with the electron microscope. The flagellar fibrils extend into the body of the protozoan to form the kinetosome. At the point of origin of the flagellum, the pellicle invaginates to form a kinetosomal vacuole around the kinetosome. The kinetoplast is formed by a transversely elongated banded structure, surrounded at some distance by a double layered kinetoplast membrane. There is no apparent connection between the kinetosome and the kinetoplast.

Notes: SYNOPSIS. Starvation of Isotricha prostoma for 72–96 hours decreased the cellular amylopectin granules and facilitated the microscopic search for bacterial feeding. I. prostoma selected and ingested only certain rods from among many types of rumen bacteria. In order to isolate the bacteria important as a food source for Isotricha, the starved protozoa were allowed to feed on mixed rumen bacteria, washed, and the crushed protozoan contents quickly cultured for bacteria. Several strains of bacteria were isolated in pure culture. Three of the rod strains isolated were rapidly ingested by I. prostoma when fed to the ciliate. In a monobacterial culture I. prostoma divided once before succumbing.

Notes: SYNOPSIS. Cultures of Trypanosoma theileri were obtained at 36° and at 37.5°C. in a blood-lysate medium inoculated with blood from three dairy cows showing subnormal milk production. The organisms were first seen after 4 days in the first subculture, reached a maximum number of about 500,000 per ml. on the 4th day of the second subculture, and attained about this same number on the 4th day of subsequent transfers. Crithidial forms predominated but trypanosomes of the blood-stream type were also numerous. Cultures were not obtained from cows with normal milk production. The infected cows, although free from helminth parasites, showed a marked eosinophilia.

Notes: SYNOPSIS. A new species of Paramecium, P. jenningsi, n. sp., from South India, is described. It is like P. aurelia except that nuclei are larger, the cell size is somewhat larger, and the macronuclear anlagen (“placentae”) have long-persisting chromatinic centers.

Notes: SYNOPSIS. The nutritional requirements of 3 isolates of Prymnesium parvum (2 Israeli, 1 Scottish) included vitamin B12 and thiamine. For comparison, 2 other brackish chrysomonads were studied: Monochrysis lutheri isolated by Droop in Scotland and Isochrysis galbana purified by McLaughlin from a culture obtained from the Plymouth laboratory.The isolates of Prymnesium parvum and Isochrysis galbana had a molecular B12 specificity like Ochromonas malhamensis: no response to Factor B, pseudovitamin B12, Factor A or Factor H. M. lutheri, in contrast, responded to pseudovitamin B12, Factor H, and Factor A.Thiamine was essential; 1.0 μg.% allowed full growth of P. parvum. The NaCl concentration for good growth was 0.3–5.0%; growth was possible from 6–12%. Dark growth was not achieved.Ammonia, as suggested from its use in suppressing outbreaks of P. parvum, was sharply inhibitory, less so at high concentrations of NaCl or at acid pH.Nitrate, ammonia, arginine, asparagine, methionine, histidine, alanine, glycine, serine, proline, leucine, isoleucine, tyrosine, aspartic and glutamic acids, acetylurea, and creatine served as nitrogen sources in both acid and alkaline media.The phosphate requirement of P. parvum and M. lutheri and Isochrysis galbana was satisfied by inorganic phosphate, commercial glycerophosphate, yeast adenylic acid, cytidylic acid, monoethyl phosphate, and riboflavin monophosphate.Laboratory cultures in defined media of the isolates of P. parvum were toxigenic to Lebistes and Gambusia. Culture fluids from alkaline media were more toxic than those from acid media, as previously noted in Israel.Culture media suitable for production of large quantities of these organisms were developed.

Notes: SYNOPSIS. Certain aspects of the metabolism of a Trichomonas batrachorum-type flagellate from the cecum of swine were studied. This trichomonad (1) oxidized glucose, mannose, maltose, sucrose, and inulin, (2) was incapable of oxidizing Krebs' cycle intermediates, (3) possessed peroxide-splitting capabilities, (4) was inhibited by only iodoacetate and arsenite, and (5) formed acid(s) aerobically. Although there was no effect on oxygen uptake, pyruvate and lactate increased the anaerobic evolution of gas(es). In addition to CO2, other gas, not absorbed by KOH, was produced anaerobically.Compared with other porcine trichomonads, the metabolism of this small trichomonad resembles most closely that of the large cecal trichomonad, T. suis. However, the smaller trichomonad had a generally lower respiratory rate, a slightly lower optimal pH, and failed to oxidize fructose, galactose, lactose, raffinose, and trehalose.

Notes: SYNOPSIS. The “dry” silver method is redescribed with special attention to the possible difficulties encountered in its use. This method first revealed the silverline or neuroformative system of the ciliates, and is considered the best method for the demonstration of this structure. The valuable results obtainable with this technique are pointed out and illustrated with appropriate photomicrographs.

Notes: SYNOPSIS. It has been assumed by others that green euglenas and derived bleached forms are physiologically equivalent except for chlorophyll and plastids. Some workers, however, have remarked upon differences which might depend on the mode of bleaching.Several hitherto undescribed chlorotic substrains of E. gracilis var. bacillaris were examined for pigment alteration, growth under a variety of conditions, and ability to withstand high temperature. These studies indicated physiological variation in the different chlorotic substrains. Although all were apparently chlorophyll-less and aplastidic, only one seemed completely achromatic. The carotenoid content of others varied. Metabolic changes manifested by altered pigmentation may reflect enzymatic variation caused by the chlorosis-inducing agents.

Notes: SYNOPSIS. Thin sections of Amoeba proteus, fixed in osmium tetroxide and embedded in methacrylate, were examined in the electron microscope. The fine structure of various protoplasmic components is described. The plasmalemma, or cell membrane, varies in thickness and structure. These variations may be due to variations in physiological state, or they may be due to differences in preparation. Along its cytoplasmic edge is always present a definite line approximately 0.01 to 0.02 μ thick. The mitochondria, or beta granules, exhibit a structure similar to that of the mitochondria of several other protozoa and comparable to that of the mitochondria of other animals. In definite association with the membrane of the food vacuole are dense, rounded particles which in size are below the limit of resolution of the light microscope. Such dense particles are much less frequently present in the hyaloplasm and in association with the plasmalemma. A possible relationship to the neutral red granules associated with food vacuoles of Paramecium is suggested. The contractile vacuole possesses a thin membrane surrounded by a much thicker circum-vacuolar zone of irregular strands which may form a three-dimensional network around the membrane. This may represent the contractile element of the vacuole. A single layer of mitochondria is closely apposed to the circum-vacuolar zone. Many small vacuoles and irregular vesicles are present throughout the cytoplasm. At times there occur groups of small, thin-walled vesicles, which may correspond to an endoplasmic reticulum. The nuclear envelope consists of a thick inner porous layer and a thinner outer layer that is continuous yet is marked by the presence of numerous small annuli, each apparently surrounding a pore. In its structure, this outer layer appears to correspond to the entire nuclear envelope of many other cell forms.

Notes: SYNOPSIS. Irradiation of Stentor coeruleus with Xray doses of 150–300 kr inhibited growth in size and fission. The irradiation also led to the development of structural abnormalities, which appeared about a day after irradiation. The inhibition of growth and fission was independent of the oxygen concentration during irradiation, but the abnormalities were produced at lower doses in nitrogen than in air. Regeneration of parts removed by cutting occurred even at the highest doses at essentially normal rate even during the period when over-all growth was completely inhibited. The conclusion is drawn that delay in fission by radiation is a secondary consequence of inhibition of growth and not a consequence of blocks in the specific morphogenetic processes required for division.

Notes: SYNOPSIS. A description is given of the formation of an unusual type of achromatic figure by two very long, narrow centrioles. The unique manner in which this structure functions in chromosomal movement is explained.

Notes: SYNOPSIS. Crosses between serine requiring and non-requiring clones from natural habitats give rise to progeny that are numerically equally distributed between the two categories. Most of the progeny from crosses between two serine requiring parental clones require serine with a few segregating out that do not need the amino acid. These data indicate that the gene or genes controlling the serine non-requirement are recessive to the wild type which requires serine. Growth of the F1 progeny was highly variable. Some clones failed to survive on serine deficient media and were therefore tentatively assigned the genotype +/+. The remaining clones were of two classes: one grew slowly on serine deficient media and was given the genotype of the heterozygote, +/s; the other grew without serine, hence was given the double recessive genotype, s/s. The F2 progeny from matings of s/s and s/s need no serine whereas the cross of +/s and s/s gave equal numbers of serine requiring and serine non-requiring progeny. The cross of two heterozygotes, +/s and +/s, yield progeny approximating the 3:1 ratio in favor of serine requiring clones. Crosses at the F3 level produced non-viable offspring in all cases except one. Progeny from this cross with the genotype s/s were mated giving rise to F4 progeny all of which grew without serine. The data support an outbreeding economy for this organism with selection in favor of the heterozygote. Although the data seem to favor a single-gene hypothysis, suppressor genes may be involved. With selection favoring the heterzygote, distorted genetic ratios make the data difficult to analyze.

Notes: SYNOPSIS. Intracardial inoculation of 1–10 million L. donovani in 0.1 ml. of ground spleen suspension from an infected animal (hamster) results in a uniform rise of parasite numbers in the untreated animal over the first 8 days after the inoculation. This rise is highly consistent from experiment to experiment.Treatment is accomplished by parenteral injection of a compound for 6 successive days in this time interval, starting 24 hours after inoculation.No known active compound in proper dosage (sodium stibogluconate, pentamidine, fuadin) has failed to show a significant suppression of the expected rise in parasite numbers. No known inactive compound has had any effect on the course of the infection.The dosage-response curve for the active compounds suggests that the method is a sensitive one. Since it takes only 8 days to complete, it is economical as well.

Notes: SYNOPSIS. It has been shown that the output of the contractile vacuole of Crithidia fasciculata increases as the concentration of solute in the external solution decreases when NaCl is the solute. The increase in output is the result of increased rate of growth as well as increased maximum size, the latter being more important in the range 0.1M–0.01M. Solutions of penta-erythritol produce the same effects as isosmolar solutions of NaCl. Body volume is not maintained constant but increases less than two-fold between 0.1M and 0.0001M. The isotonic concentration of NaCl is estimated as 0.12M. It is not possible to demonstrate any effect of concentration of the external environment on the endogenous rate of oxygen consumption. A linear relationship between output and calculated osmotic gradient across the cell membrane has been shown in the concentration range 0.1M–0.01M. Absence of this relationship, and failure of body volume to increase as predicted, in solutions more dilute than 0.01M are interpreted as indications that other processes probably become predominant in these solutions. It is concluded that the contractile vacuole of this flagellate is incapable of maintaining absolute constancy of internal osmotic pressure and body volume but prevents much of the change expected on physical grounds.

Notes: SYNOPSIS. The rather rarely found holotrichous ciliate Pseudomicrothorax dubius, generally considered in the most authoritative literature to be a member of the order Trichostomatida, more likely belongs in the Hymenostomatida. Its curious combination of trans-ordinal characteristics, however, makes difficult exact systematic allocation of it and of the congeneric species P. agilis. The provocative morphological features include: a gymnostome-like cytopharyngeal “basket”; a tetrahymenal buccal apparatus, with membranelles comparable with those of primitive hymenostomes; an advanced semi-autonomous type of stomatogenesis; and sensory bristles, flattened rigid form, and restricted ciliature reminiscent of certain spirotrichs. Brief discussion is presented concerning the influence of modern ideas of ciliate classification upon what is considered the proper taxonomic position of the genus.

Notes: SYNOPSIS. A new fresh water species of Actinosphaerium is described, the fourth member of the genus. Some of the more significant of its diagnostic traits are: 1) the Actinophrys-like nuclei with peripheral nucleolar granules and without central rosette-shaped nucleoli, 2) the occurrence of some nuclei in the ecto-endoplasmic border and the insertion of axial filaments on them, and 3) the low ratio of endoplasm to ectoplasm.

Notes: SYNOPSIS. In cultures of the marine dinoflagellate Gonyaulax polyedra grown with alternating light and dark periods of 12 hours each, at least 85% of all cell divisions which occur in a day take place during a 5-hour period spanning the end of the dark period and the beginning of the light period. A very distinct maximum in the number of recently divided cells occurs at about the time the light period begins.This diurnal periodicity in cell division is lost after 4 to 6 days in continuous bright light, but will persist for at least 14 days in continuous dim light. The period of approximately 24 hours under constant conditions is only slightly altered by varying light intensity and temperature, both of which factors are known to affect markedly the generation time. The time at which cell division occurs is therefore postulated to be controlled by some sort of rhythmic or clock mechanism.Similarities between the cell division rhythm and the endogenous rhythm of luminescence in this organism are discussed. The occurrence of a glow, or steady light emission of low intensity, at about the time of cell division, is described, and it is suggested that this glow may result from cellular changes accompanying certain stages of cell division.

Notes: SYNOPSIS. The photographs illustrate male and female gametes before fertilization, several progressive stages in the entrance of the male gamete into the cytoplasm of the female, cytoplasmic fusion of gametes, loss of extranuclear organelles of male gamete, retention of extranuclear organelles of female gamete, movement of pronucleus of male gamete to that of female, progressive stages in fusion of pronuclei, and the formation of the zygote which possesses the extranuclear organelles of the female gamete. Some abortive attempts at fertilization, resulting from failure of gametes to differentiate, are shown.

Notes: SYNOPSIS. Detailed directions are given for the preparation of a simplified assay medium and of natural materials for assay of pteridines with Crithidia fasciculata. Unconjugated pteridines in natural materials which also contain conjugated pteridines (folic and folinic acids) can be assayed by destroying the conjugated pteridines with acid hydrolysis, which does not appreciably alter Crithidia-active unconjugated pteridines. The widespread occurrence of unconjugated pteridines and their significance in such processes as photoreception are discussed.

Notes: SYNOPSIS. Photokinesis or the non-directed rate of swimming of Euglena gracilis for various light intensities was studied. The rate of swimming in white light was found to increase with light intensity until it reaches 0.16 mm./sec. at a saturation of 40 ft. candles, and then decreased with increasing light intensities. Polarized light appeared to be more effective (0.18 mm./sec. at 13 ft. candles) than non-polarized light.The action spectrum for photokinesis showed two peaks, a major one near 465 mμ, and another in the neighborhood of 630 mμ, having the values of 0.18 mm./sec. and 0.16 mm./sec. respectively at an intensity of 4 ft. candles.The action spectrum for phototaxis, or directed orientation, had a peak near 420 mμ and showed a maximum near 490 mμ. Both dark-grown and dark-adapted Euglena showed spectral peaks similar to those of the light-grown cells. For polarized light, the action spectrum had two additional peaks at 468 mμ and 508 mμ. The polarized light effect may indicate more than one light-absorbing pigment within the “eye spot” or that other pigments within Euglena were absorbing.

Notes: SYNOPSIS. Four new species of Eimeria are described from small mammals in Liberia. These are: E. levinei, sp. nov. from a free-tailed bat, E. firestonei, sp. nov., and E. milleri, sp. nov., from a shrew, and E. putevelata, sp. nov., from a striped grass mouse.

Notes: SYNOPSIS. A new species of Stentor is described, a fresh water form, medium sized, with cerulean blue pigment, and characterized by retractable feeding organelles.

Notes: SYNOPSIS. Coprozoic protozoa from elk, bison, bear, moose, coyote, marmot, cattle, horse, sheep and man were kept in feces at 4° C. for 2–6 months. During that time in most of the samples there developed the flagellates Cercomonas sp., Copromonas ruminantium and Monas communis; the amoebae Vahlkampfia sp. and Sappinia diploidea, and ciliates of the Nyctotherus type, and an unidentified smaller species. There was a correlation between numbers of protozoa and bacteria. The same species of protozoa in soil or in soil mixed with boiled feces failed to live. Coprozoic protozoa may require certain essential metabolites from bacteria as do true parasites. The wide variation in appearance of cysts made it practically impossible to identify the protozoa with certainty in that stage. Reliance had to be on motile forms which readily developed in the cold cultures.

Notes: This paper proposes that salary structures and the development of salaries over time be considered within the framework of the distribution of income over time. In particular, it examines certain salary scales in the U.S. and the progressions of typical individuals’ salaries during the period 1948–1969, in comparison with the percentile distributions of household income in the same period, as reflected by the Current Population Survey of the Bureau of the Census.

Notes: This paper assesses the role of inventive and innovational activity in the growth process of Canada, a country which relies overwhelmingly, some 90 per cent, on the importation of technological advances and operational know-how from abroad. Canada has prospered under this arrangement but at a price. With technology came foreign capital, foreign management and substantial foreign control. To lessen Canada's dependence on foreign know-how, this country has embarked on an expanded R & D programme. But the pay-off from these efforts has been less than expected. To throw a light on the subject, the results of two new surveys are presented: one a sample survey of patents granted, the other an interview survey of large corporations. Questions examined include sources of know-how and technological advances, utilization of inventions and abandonment of innovations, R & D and innovations, domestic and foreign innovations, and the profitability of innovations. Aggregative assessment is supplemented by disaggregative analysis using cross-section and industry data.

Notes: The paper presents forecasting models for (1) the share of competitive imports in the total demand for a commodity group and (2) the level of demand for competitive imports of a commodity group. The two forecasting models are used, respectively, with (1) input-output models which incorporate market share parameters as one vector of coefficients and (2) input-output models which assume imports have been determined autonomously. It is shown that these two types of input-output models can be made workable by prefixing one or other of the import forecasting models to the input-output model. Tests are made of the forecasting ability of the combined models.

Notes: This article is an extension of an earlier article dealing with gains and losses from changes in the terms of trade. The object of the present article is to show how gains and losses in foreign trade are distributed among the branches of domestic industry. To this end, price changes for gross domestic product at factor cost in each of 25 branches of industry over the period 1949–1965, computed where possible by the double deflation method, are compared with the change over the same period in final demand—i.e., consumption plus gross investment.

Notes: This paper develops a method for estimating long-run trends in income growth from the data available on a country's currency stock. The method is applied to nineteenth-centry Brazil. The results indicate that contrary to earlier beliefs, the country as a whole probably experienced only moderate growth in per-capita income during the nineteenth century. The approach may also be useful for other countries where data shortages preclude estimates of national income by conventional methods.

Notes: This paper discusses the relevance of the conventional national accounts systems to the traditional African economy and concludes that they contribute little because they omit certain economic activities and fail to recognise the reciprocity between social and economic activities. Social accounting is thus more relevant. Lack of statistical data may make it necessary to conduct special surveys and in some cases a tribe or village or economic region may be a more useful accounting unit than a nation. A modified system of accounts is suggested, based on the frame work of the four consolidated accounts of the SNA. It provides linkages to many more nonmonetised activities. Other linkages would be provided through supporting tables emphasising social activities and transfers. A system of transactor accounts in matrix form is also suggested. In the case of communities smaller than the nation several external transactor sectors could be included. It is recognised that the problem of evaluation of social activities and a number of economic activities remains to be solved and it is concluded that “time spent” may be the only common unit or value to equate such activities.The final section deals with investment in human resources and proposes a balance sheet approach to indicative planning. This exercise would be related to demographic projections in several variants. Other factors to be analysed dynamically would be education and health status, public finance and, ultimately, distribution of income and wealth since it is noted that the process of monetisation is having an impact which may have important welfare implications.

Notes: In this paper the author adds some further empirical tests of his theory of income distribution. This theory (cf. this Review, Series 16, Number 3, September 1970, p. 221 ff) sees income distribution as the distribution of prices of production factors, especially labour, of different quality and prices as the effect of demand and supply factors. The quality of labour is represented only by the number of years of schooling. Its supply is described by the actual numbers of people having each of the possible years of schooling; this frequency distribution can be characterized by its average and by some measure of its dispersion or by one of its deciles (in particular the highest) expressed in terms of its median. The demand for the various qualities of labour can be supposed to be reflected by (i) total demand for commodities, but (ii) more accurately by the percentage of third-level educated people used in and weighted by the size of the four main sectors of production: agriculture, manufacturing, trade and transport, and other services. Extensive material collected and reworked by Professors B. R. Chiswick for the U.S.A. and Canada and T. P. Schultz and L. S. Burns with H. E. Frech III for the Netherlands is used in cross-section tests to explain variations in income distribution in the states of the U.S.A. and the provinces of Canada and the Netherlands. The results can be found in the tables. While further increase and smaller dispersion in years of schooling, according to some of the findings presented, would only moderately reduce the degree of inequality in the U.S.A. and Canada, more result seems to be possible according to other findings, including those for the Netherlands. In the latter category the second demand index mentioned above has been used. This paper is one of several devoted in various ways to the testing of the same theory.

Notes: Statistics for developing countries often are misunderstood and misinterpreted because the published data do not distinguish between the economically modern and the traditional sectors. The purpose of economic development is to move a nation from the traditional, or largely non-monetary, subsistence agriculture type of life, to the modern or money oriented and technologically developed type. Statistics of national accounts, the economically active (the working force), and other topics often fail to be useful for economic development purposes because they are presented for the totality of the country and do not show the modern-traditional sectors separately.In addition, data are often misinterpreted and used incorrectly because the development economists do not understand the nature of the data—how they were collected and what they really signify. This point is illustrated with the economically active statistics. Finally, a plea is made for more statistics and information about families.

Notes: This paper deals with some results of an extended investigation which was carried out by the German Institute of Economic Research, Berlin, and the Ifo-Institute, Munich, and financed by the Stiftung Volkswagenwerk. For 29 sectors of manufacturing Cobb-Douglas production functions have been calculated, based on quarterly figures 1958–1968 of value added, input of hours worked, input of utilized capital stock (net of scrappage), and of potential value added, potential labor input and total capital stock. The income distribution is used as production elasticities. For each of the 29 sectors 12 time series of quarterly indices of total factor input and technical change have been computed, using utilized data (variation 1-6) and capacity data (variation 7-12). Two different time series of α are used, taking quarterly interpolated data (variation 1, 3, 5, 7, 9, 11) and the geometric mean 1958–1968 (variation 2, 4, 6, 8, 10, 12). Moreover three different parameters of homogeneity are introduced, taking r= 1 (variation 1, 2, 7, 8), r= 1.1 (variation 3, 4, 9, 10) and r= 1.25 (variation 5, 6, 11, 12). Seven of the 29 sectors show a very high sensitivity of the rate of technical change due to the assumed r, six sectors a rather high sensitivity. Ten of the 29 sectors show a rather small sensitivity of technical change due to the assumed r, six sectors a very small or even negative sensitivity, i.e. an increasing r creates an increasing technical change. These results can be explained by taking account of the fact that total factor input in many branches increased very slowly or even decreased (labor input alone decreased in nearly all branches). A hierarchy of technical change has been calculated; this hierarchy is difficult to explain, because fast growing industries as well as industries with a small or a negative growth rate of output rank in both the leading and the last group of technical change. Very high rates of output result in high rates of technical change (chemicals, mineral oil refining, plastics manufactures), but some industries with a rather small growth of output (shipbuilding, fine ceramics, steel drawing, and cold rolling mills) show a high rate of technical change too.

Notes: An underlying theme in this paper is that the differences in approach in this area arise partly from the complexity of the phenomena in the real world being studied, the implications of this interrelated complexity for unbiassed and efficient estimates of the structural relations, and the problems of getting an adequate number of observations of the required form.Two distinct approaches have been used in the study of marginal and total factor productivity. One approach is to use the factor shares in national income as weights to combine the individual factor inputs to make an index of total factor input, and to use a factor's relative share to measure its marginal contribution. The second approach is to estimate the production relation from the data being used, and derive the marginal contribution of the productive factors to output from the estimated relation. The longest parts of the paper review the procedures followed to cope with the main problems in the real world, and the strengths and limitations in the two approaches. The discussion emphasizes the issues for the economy as a whole, and touches only briefly on the issues in disaggregation.Three major themes are emphasized in the conclusions to the paper. One is that many of the problems, the differences in view, and the controversies grow out of the range of interrelated issues in practical applications. A second major theme is that most of the attempts to solve particular issues by those using the factor shares approach are rather similar to those followed by researchers estimating the production relations directly. A third theme is to encourage more studies that will look at the interconnections between production relations and income distribution, from the points of view of both economic theory (and its predictions about the relevance to concrete applications) and statistical estimation.

Notes: This paper summarizes the results of several studies on total factor productivity of twenty-five countries over the period 1950–1965. Some methodological issues which underlie the derivation and calculation of the familiar partial and total factor productivity indices are discussed. Though evidence on labor productivity for a large number of countries is presented and discussed, the main thrust of the discussion is in terms of the determinants of total factor productivity. The quantitative and qualitative contributions of labor and capital to growth of income are assessed with special attention to the contrasting patterns of these contributions among developed and developing economies. The problems of acceleration and retardation of the growth rate of some economies are considered and possible explanations are offered. Variations in the magnitude and sectoral distribution of the growth rates in several countries over this period are examined. Finally, areas for further research in comparative economic growth are suggested.

Notes: This paper discusses the estimation of the CES Production Function with Hicks-neutral technical change, and gives the results of an empirical study based on time series data (quarterly values) for sixteen industrial sectors in the Federal Republic of Germany (including West-Berlin), 1958–1968. The validity of the basic assumptions of the production model used in this investigation—neutrality of technical change and perfect competition—is tested by estimation of alternative specifications of the equations of this model. For this purpose two different methods of estimation were used.

Notes: Developing countries which typically have import surpluses and inflationary pressures because of insufficient savings are prone to use indirect taxes on imports (Tm) and subsidization of exports (Sx) in order to prevent deterioration of the balance of trade. If these substitutes for devaluation are included in the net indirect tax component of product at current market prices (Ym) the import surplus is likely to be understated, and Ym upward biased. This distortion will be avoided if imports and exports are measured at effective exchange rates (ER), that is, at official rates (OR) plus Tm and Sx respectively, and if (Tm - Sx) is deducted from the net indirect tax component of Ym. Only in this manner become imports and exports consistent with the other uses and resources at market prices and can be articulated with them. At base-year prices the volume index of product at OR diverges from that of ER to the degree that the composition of imports and exports in regard to tax and subsidy rates computed ad valorem significantly changes.Such a case is similar to that of the price indexes of imports and exports moving in diverging proportions: the trade balance at base-year prices will differ from that at current prices. The resulting discrepancies in national accounts have led to proposals of deflating, for example, exports by the price index of imports. Suchlike approaches are incompatible with the principle of national accounting that prices are supposed already to measure substitution values. Deflating exports by import prices means reintroducing substitution values, as does, for example, deflation of incomes by a consumer price index. Correspondingly, since the trade balance at ER conceptually expresses the value of imports at domestic market prices as compared to the corresponding domestic market value of exports, and if at ER the trade balance diverges from that at OR, the former balance has an important meaning (as has the trade balance at base-year prices as compared to that at current prices) and the resulting discrepancy between the two measures should not be removed merely for the sake of accounting smoothness.In contrast to the market price approach, the measurement of product at base-year factor cost is indifferent to the measurement of the trade balance at ER and at OR.It is, therefore, proposed in countries in which part of import taxation and export subsidization substitutes for devaluation, to record imports and exports in the national accounts at effective exchange rates, and to correct the net indirect tax component of product correspondingly. Imports and exports at official exchange rates should be shown within the balance of payments, and the latter separately as a memorandum item.

Notes: Changes in many output determinants contribute to growth. An analysis of the sources of growth is an allocation of changes in output among these determinants. Total factor input and output per unit of input condense all determinants into two groupings. Misinterpretation of results is common because authors presenting either detailed or summary results often provide no complete or precise description of their classification of determinants, and readers ignore even the information provided. The classification suggested in this paper is detailed enough to bring out points at which description is required but often overlooked. Some effects of alternative estimating procedures on classification are described.The relative usefulness and practicality of possible alternative classifications also need consideration and discussion. This paper is concerned with general purpose classifications, appropriate for analysis of actual series measuring a country's total output, that are suitable for present use but will also accommodate useful detail that may later become feasible. A desirable classification will so specify determinants that (1) they both unite cause with effect and correspond to the economist's method of analysis so that his set of tools can be brought to bear; (2) they do not contribute to growth if they do not change; and (3) they conform as well as possible to practical possibility of estimation. Among several points considered fundamental are that the complete contributions of advances in knowledge and of resource reallocation each appear as an entity. They should not be dispersed among inputs or other determinants. It is less clear whether economies of scale should be a separate determinant or their contribution be dispersed.