Cll PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



robust serpent, and that on the whole he considers that, if all the 

 vertebrae belong to the same genus, and that genus be Paleryoc, the 

 analogy of the genus is more with Python than with Eryoc. At the 

 same time there are, in the same deposit, smaller vertebras, belong- 

 ing probably to younger individuals of the same species, and which 

 are more close in their resemblance to Paleryoc. The discovery of this 

 little nest of snakes in Switzerland, apparently the same as those of the 

 Bracklesham Clay of England, is a most interesting fact as regards 

 the distribution of fossils. Some Chelonian remains found by MM. 

 Gaudin and De la Harpe at Mauremont close the number: they appear 

 to show the former existence of a small Emys and of a small Land Tor- 

 toise, scarcely determinable ; and at the same time they have afforded 

 materials for the restoration of the carapace, and partly of the breast- 

 plate, of a species which is assigned to the new genus and species 

 Dithyrosternon valdense, Pict. and Humb. It unites many of the 

 characters of the Land Tortoises, associated with some of those of 

 the Emys. The generic name implies that the shell has two move- 

 able doors or valves. There are living genera which have the double 

 valve, such as the Cistudo, where there is, however, no fixed portion 

 of the breastplate between the valves, which simply move on a 

 hinge ; and the Cinosternum, in which the analogy as regards the 

 two valves is complete, but in all other respects it fails. 



Appended to the 9th part is a list of the Yertebrata of the Eocene 

 Fauna found in the siderolite deposits of the Canton de Yaud. 



Mammalia — Pachydermata. — 1. Palaeotherium medium, Guv. — 2. 

 Palasotherium curtum, Guv. — 3. Plagiolophus minor, Pomel, 

 Palaeotherium minus, Guv. — 4. Rhagatherium valdense, Pictet. 

 — 5. Hyracotherium siderolithicum, Pictet. — 6. Oplotherium. 

 — 7. Dichobune Campichii, Pictet. — 8. Dichobune, species near 

 to but a little larger than D. cervina, Owen ; from isolated 

 teeth. — 9. Dichobune, smaller species, also from teeth alone. 



Carnivora. — 1. Amphicyon, species of the size of the Conguar; 

 from teeth alone. — 2. Cynodon, probably new species of the 

 size of C. lacustris, Gervais, from teeth alone. — 3. Indeter- 

 minable, of the size of the Ocelot. 



Cheiroptera. — 1. Yespertilio Morloti, Pictet. 



Hodentia. — 1. Theridomys siderolithicus, Pictet. — 2. Sciurus. — 

 3. Spermophy tus ? 



Reptilia — Sauridia. — 1. Crocodilus Hastingsiae, Owen. — 2. Lacerta. 



— 3. Placosaurus rugosus, Gervais. — 4. Saurian of extinct 



species, probably belonging to the group of Iguanas. 

 Ophidia. — 1. Python. — 2. Python or Paleryx. 

 Chelonia. — 1. Dithyrosternon Yaldense, Pictet <$f Humbert. — 2. 



Cinixys ? — 3. Emys, large species. — 4. Emys, small species. 



— 5. Testudo, small species. 



Most of these fossils were obtained by the labours of either MM. 

 Gaudin and De la Harpe, or of Professor De Morlot ; and as the 

 illustrations, both of them and of the Mollusca previously noticed, are 

 extremely well drawn and lithographed, the work may be justly 



