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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Zoomorphology 62 (1968), S. 307-362 
    ISSN: 1432-234X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The digital setae of gekkonids and anoline lizards show free ends which consist of disk-like thickenings, deepened towards their centre. The climbing ability of the reptiles investigated depends mainly on adhesion processes.
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  • 2
    ISSN: 1432-234X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Kurz nach einer Hdutung wird bei Tarentola m. m. bereits die übemächste Epidermisgeneration — und somit auch die der Haftborsten —angelegt. Das geschieht vornehmlich in der Oz- (Oberhäutchenzellen-) und in der Hs-Schicht (clear layer). Zunächst entstehen die Aufspaltungen der Haftborstenenden, indem Keratinfilamentbündel nach einem bestimmten System von den Oz-Zellen aus in die Hs-Zellen einwachsen. Auf these Weise fungieren die Zellen der Hs-Schicht als Matrix der Haftborsten. Nach Abschluß dieses Prozesses werden die eigentlichen Haftborsten gebildet unter gleichzeitigem Auseinanderrücken der Hs- und Oz-Schichten. Die Hs-Schicht behdlt ihre Matrizen-Funktion bis zur anschließenden Häutung bei.
    Notes: Summary In Tarentola m. mauritanica the next epidermis generation but one and therefore the adhesive setae of the generation after this begin to develop shortly after a skin has been shed. This development takes place principally in the horny layer (Oz) and the clear layer. First bundles of keratin filaments radiate from the horny layer into the clear layer, thus giving rise to the split distal parts of the adhesive bristles. Thus the cells in the clear layer act as a matrix for the setae. When this stage is complete the formation of the setae proper begins, while the horny layer and the clear layer become separated from each other. The clear layer retains its function as matrix for the setae until the next time a skin is shed.
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  • 3
    ISSN: 1432-234X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Die borstenführenden Hautsinnesorgane vonTarentola mauritanica sind in die Epidermis eingesenkt und besitzen aufgrund ihrer Hüllzellen eine verdickte Basis. Jedes Organ befindet sich jeweils über dem dazugehörigen Nerv. Nach seinem Eintritt in das Organ kann man Axone beobachten, die die Sensille in distaler Richtung durchziehen. Die Hüllzellen umgeben in der Hauptsache zwei gro\e epidermale Zentralzellen, zwischen denen die Axone unter starker Invagination verlaufen. Die Zentralzellen reichen bis zur distalen Zellschicht der Äu\eren Epidermisgeneration. Die Axone invaginieren nach Verlassen des Zentralzellenbereichs in diese Schicht und bilden dort 10–15 Terminalblasen, die als Stellen der Reizaufnahme anzusehen sind. Sie liegen nahe unterhalb des Sensillendeckels, der oft mehrere lange Zentralborsten aufweist. Eine Auslenkung der Borsten dürfte sich als Deformation des Deckels auswirken, der wesentlich dünner ist als das OberhÄutchen au\erhalb des Sensillenbereichs. Die Bedeutung der Sensillen auf den Zehenrandschuppen liegt in der Kontrolle der Zehenbewegung und in der FÄhigkeit, Wasser aufgrund der OberflÄchenspannung zu perzipieren. Bei Kontakt mit feuchten Medien werden die Zehen augenblicklich dorsal aufgerollt und die Haftborsten so vor Verklebung geschützt.
    Notes: Summary The ultrastructural organization of the setae-bearing sensilla has been elucidated with regard to their position on the scales, their surface structure and their presumable functions. These sensilla have a thickened basis caused by enveloping epithelial cells. Each organ is situated above the appropriate nerve. Entering the organ, this nerve ramifies into axons, which continue between two great central-positioned cells of epidermal origin as far as to the top of them. The central cells end beneath the distal layer of the outer epidermal generation. Leaving the central cells at their top, the axons invaginate into this layer and form, corresponding to the number of axons, 10–15 terminal vesicles. These terminals are — according to recent ultrastructural findings — presumably able to registrate (mechanical) stimuli. The terminals are embedded in masses of tonofibrils, especially at their bases. At the flattened top of the organ long setae are situated centrally but without any direct contact to lower parts of the organ. Mechanical bending of the setae will deform the top of the sensillum which will be recorded by the terminal receptors described. The movement of the toes is controlled by the sensilla of the scales surrounding the toes, which is important for the climbing mechanism. A decisive function of these organs is the perception of water or other wet substrata. When touching this, the geckos will immediately roll up their toes thus protecting their bristles of the footpads from sticking together.
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  • 4
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The tail of Teratoscincus scincus has dorsal scales that have tubercles on their dorsal and ventral surfaces. Sounds are produced when these rub past each other as the excited animal moves its tail. The relative movement of scales is intensified by caudal torsion. The frequencies of the sounds cover a range from 9 to 25 kops and thus, differ from those produced during vocalizations.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 177 (1977), S. 325-330 
    ISSN: 1432-0878
    Keywords: Reptilian scales ; Receptors ; Innervation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In gekkonids, the scales bordering the toes or the adjacent tissue possess subepidermal and intraepithelial receptors in addition to setae-bearing organs. The position of subepidermal lamellated corpuscles seems to be correlated with the size of the species. The larger the adult animal the more frequently is this type of receptor found laterally in the toe. This can be explained in connection with the vibration-sensitive function of lamellated receptors. Intraepithelial axon terminals were found close to the setae-bearing sensilla in one species only. They are surrounded by numerous tonofibrils and may function as receptors for mechanical (pressure-) stimuli.
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  • 6
    Publication Date: 2008-03-01
    Description: The general integument of reptiles is traditionally defined as being dry, but we report here the discovery of unicellular mucoid glands (UCMG) in the dorsal skin of lizards of the genus Phelsuma (Gekkonidae). To this end, the skin of these lizards and of some others for comparison was studied by scanning electron microscopy and transmission electron microscopy. These photographs showed that the development and function of the UCMGs are related to the skin’s sloughing cycle. The UCMGs differentiate at scattered locations from Oberhäutchen cells of the inner (new) epidermal generation, above the differentiating β-keratin layer. While the inner generation matures, the UCMG increases in size; unlike the surrounding Oberhäutchen cells, it does not develop the spinules that characterize gecko skin. When, upon sloughing, the inner generation becomes the new outer generation, and the Oberhäutchen forms the skin surface, the UCMGs, several per scale, dot the surface as mucus-inflated “blebs” projecting from the surrounding spinulate Oberhäutchen, each nesting in a shallow pit of the underlying β-keratin. On the surface, the UCMGs rupture and the mucus appears to dissipate in cords, flowing over the tips of the spinules, and incorporating minute foreign bodies. It is concluded that, due to the low wettability of the spinulate surface (derived from the spacing of the spinules), the cords brush off easily, with the mucus functioning as a cleaning agent. ©2007 Springer-Verlag
    Print ISSN: 0028-1042
    Electronic ISSN: 1432-1904
    Topics: Biology , Chemistry and Pharmacology , Natural Sciences in General
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