ALBERT

Description: On 13 December 1990 Prof. Dr. Cornelis (Kees) Kalkman retired from the positions of Professor of Plant Systematics and Scientific Director of the Rijksherbarium/ Hortus Botanicus by presenting his valedictory lecture to the academic community of Leiden University and the assembled Dutch Botanical world. The day after, circa 170 staff members and partners joined in the research institute for a memorable farewell party, culminating in a show around the personality of the parting Director. \nBom in Delft on 5 May 1928, Kalkman used the opportunity of early retirement at the age of 62, after a long term as an active and successful administrator and coordinator of research and teaching in plant taxonomy in Leiden. This now offers him the possibility to return to taxonomic work on Rosaceae and on writing a textbook on economic botany. He also continues for a couple of years as Chairman of the Flora Malesiana Foundation, and is as such active in further internationalisation and speeding up of the Flora project.

Description: The leaf, twig, and nodal anatomy of Alzatea, Axinandra, Crypteronia, Dactylocladus, and Rhynchocalyx is described in detail. This family, as newly delimited by Van Beusekom-Osinga and Van Beusekom, appears to be very heterogeneous, a conclusion supported by the wood anatomical diversity reported in another paper. The nodes may be simply unilacunar, unilacunar with a complete girdling trace, of the common gap (or split lateral) plus median trace type, or trilacunar. Cortical bundles may be present in addition. Further diversity is present in e.g. cuticular texture, stomatal type, hypodermal development, arrangement of vascular bundles in petiole and midrib, mechanical support of the veins, the crystal complement, foliar sclereids, and cork origin. Anatomical evidence only supports the Myrtalean character of all genera, and a close mutual affinity of Axinandra and Crypteronia. These genera, together with Dactylocladus show several features characteristic for some Melastomataceae, which family with its wide anatomical range would also cover most of the anatomical diversity of Lythraceae, Sonneratiaceae, Oliniaceae, Alzatea, and Rhynchocalyx. Rhynchocalyx appears to be closer in its anatomy to some Lythraceae, Oliniaceae, and Melastomataceae than to the other members of Crypteroniaceae. Alzatea shows affinities with all families mentioned, but remains problematic with its trilacunar node not known to occur in the other families. The complex pattern of overlapping anatomical ranges of Crypteroniaceae s.l., Melastomataceae, Lythraceae, Oliniaceae, and Sonneratiaceae may be interpreted as evidence of intimate relationships between these families.

Description: The leaf anatomy of all 33 species of Heisteria is described, based on a study of 143 specimens. There is a considerable amount of diversity in stomatal type (anisocytic, anomocytic, cyclocytic, laterocytic or paracytic), in occurrence and type of mesophyll sclereids, and of fibre bundles along the leaf margin. Outline and thickness of anticlinal epidermal cell walls, cuticle thickness, crystal complement, and stomatal size also vary, but often below the species level. The leaf anatomical diversity can be used for recognising 8 groups of varying distinctness in Heisteria. H. asplundii and H. skutchii with laterocytic stomata, and H. pentandra and H. scandens with paracytic stomata constitute the two most distinct infrageneric groups; the other six groups appear mutually more closely related and are partly linked through intermediates. A tentative phylogenetic classification of Heisteria and a discussion of the position of Heisteria in the Olacaceae is given.

Description: On 2 September 1992 Rob Geesink died a week before he would have reached the age of 47. He had been associated with the Rijksherbarium from his student days in the sixties onwards. For his MSc programme he successfully revised the Portulacaceae for Flora Malesiana and carried out an experimental-ecological study of the genus Bangia (red algae). In 1971 he received his congratulatory (\xe2\x80\x98cum laude\xe2\x80\x99) MSc degree. From 1972 to 1974 he was executive taxonomist in the Thai-Dutch cooperative project for the Flora of Thailand, a post during which he made four botanical explorations. In 1976 he was finally appointed on the staff of the Rijksherbarium, from 1987 to early 1990 as Project Leader of the research group for Tropical Phanerogams. \nRob\xe2\x80\x99s talents and interests covered a unique and broad range; from handy-man to theorist, and from efficiency improvement in the daily routine of plant collecting and taxonomy to the application of information theory in evolution. As a student he impressed his supervisors Van Steenis and Den Hartog, when he developed a device to shake and aerate algal cultures with the aid of spare motorcycle parts. Later \xe2\x80\x98inventions\xe2\x80\x99 included the use of a bottle cap in combination with an electric cigarette lighter to boil and rehydrate delicate herbarium fragments, a noise-reducing exhaust for engines, and a do-it-yourself altimeter for trees. His eye for the practical is also apparent from the enthusiasm with which he took the initiative to produce, together with other colleagues, a fully revised version of Thonner\xe2\x80\x99s \xe2\x80\x98Key to the Families of Flowering Plants\xe2\x80\x99, from the production of a punched card key to the genera of SE Asian Leguminosae, and from his analysis of practical changes needed to ever complete Flora Malesiana. During his PhD study, initially aimed at a revision of the genus Millettia, but later modified to a generic treatment of the tribe Millettieae (\xe2\x80\x98Scala Millettiearum\xe2\x80\x99, published in 1984), Rob had felt a strong need for a more thorough knowledge of theoretical aspects of systematics, especially of phylogenetics. Insights developed during broad and intensive background reading were shared with students and colleagues through introductory manuals and in regular reading and discussion circles which Rob initiated both in Leiden and Wageningen, and which are continued after his death with a nation-wide attendance. In the last years Rob was especially interested in the newly developed theory of evolution as an entropic process as well as in the philosophy of systematic science. He must be given credit for introducing modern cladistics and historical biogeography to the Rijksherbarium.