22i M. Vauthier on a new Specks of Epeira. 



poda, this genus should be placed in that of the Monothalamous 

 Cephalopoda, near the Argonantqe, Avhose characters, as given by 

 M. Lamarck, cannot apply to it, since the shell of the latter is 

 very thin, whilst that of the Bellerophontes is very thick, and 

 instead of the double keel of the Argonautas, we find in the 

 middle of the back of the Bellerophontes a single keel, dividing 

 the shell into two equal parts. The latter differ moreover from 

 the former, in the whorles of the spire being very numerous, 

 whereas the Argonautae are curved, but not convolute, so that 

 nearly the whole of the shell is perceptible, the summit of which 

 is extraordinarily obtuse. 



The Argonautae and the Bulla? are the shells which the Belle- 

 rophontes appear to resemble most, but still differ from them so 

 much, that it seems right to form the latter into a separate genus. 

 In that case they may be described by the following characters : 

 Shell free, univalve, not chambered, spirally convolute, depressed, 

 shuttle-shaped? (formant la navette) — the last whorle of the 

 spire inclosing all the rest ; aperture very oval, receiving, in the 

 middle part, the back of the shell. 



AitT.XXVI. Description of anew species of Arachnides, of 

 the Genus Epeira, ofM. Walckenaer. By C. Vauthier*. 



[With a Plate.] 



Tins new species of Arachnides, originally from Java, which I 

 shall describe under the name of Epeira curvicauda, was commu- 

 nicated to me by M. Leman. Its singular organization, and the 

 perfect state in which it is preserved, have determined me to make 

 an analytical drawing of it, and to publish its description. 



Not having found in the collection of the Museum of Natural 

 History, which I have carefully examined, nor in the authors 

 whom I have consulted, any individual perfectly identical with 



* Translated from the Annates des Sciences Natufelles, vol. i. p. 361. 



