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| Dullemeijer, P.; Povel, G.D.E.. |
| INTRODUCTION A controversial point in the understanding of the feeding mechanism of viperid snakes is the use of the poison fang in the swallowing mechanism. Some authors believe that the poison fang takes an active part in the swallowing act, although the majority supports the view that the fang is, at least partly, held down (Klauber, 1956). Which kind of construction in the jaws is responsible for the difference between the actions of the fang in striking and swallowing again is a matter of dispute. The pterygoid-ectopterygoid joint, which by most authors (Kathariner, 1900; Willson, 1908; Haas, 1931; Klauber, 1939, 1956) is considered stiff or immovable, may play a crucial role. There is also some disagreement on the strike being either a stab (Van... |
| Tipo: Article / Letter to the editor |
Palavras-chave: 42.82. |
| Ano: 1972 |
URL: http://www.repository.naturalis.nl/record/318611 |
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| Povel, G.D.E.. |
| The data set of the so-called main branch of Miocene Gyraulus, collected and measured by Mensink, has been re-examined by means of multivariate methods. New information was obtained by presenting the percentage of specimens which have a keel on the second or third whorl in a bivariate way. In an earlier multivariate analysis Lindenberg & Mensink used only six characters, in the present paper an additional two characters have been used. However, as the number of characters is small, some of them have not been adequately measured, and because the identification of part of the specimens was questionable, the results may still be insufficient. |
| Tipo: Article / Letter to the editor |
Palavras-chave: 38.22. |
| Ano: 1992 |
URL: http://www.repository.naturalis.nl/record/317282 |
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