238 RODENTIA. 
27635. Two specimens of part of the upper and lower dentition ; 
from the Lower Miocene of Sauvetat (Puy-de-Dome). 
Croizet Collection. Purchased, 1848. 
27760. Several specimens of the upper and lower jaws; from the 
Lower Miocene of Sauvetat. One specimen of the man- 
dible shows the milk-molars. 
Crozet Collection. Purchased, 1848. 
27760a. Part of the left.ramus of the mandible of an immature 
individual, showing the premolar partly protruded; from 
the Lower Miocene of Sauvetat. 
Croizet Collection. Purchased, 1848. 
27760 b. The first three right lower cheek-teeth of a young indi- 
vidual, with the milk-molar in situ; from the Lower Mio- 
cene of Sauvetat.  Croizet Collection. Purchased, 1848. 
27694a. Part of the left ramus of the mandible; from the Lower 
Miocene of Puy-de-Dome. No hastory. 
M. 1628. The greater part of the left ramus of the mandible, show- 
ing the four cheek-teeth ; from the Upper Eocene of Caylux 
(Tarn-et-Garonne), France. This specimen agrees in size 
with the one from Ronzon figured by Filhol in the Ann. 
Sci. Géol. vol. xii. pl. vi. fig. 16. Schlosser’ refers a very 
similar specimen from the Upper Eocene of Caylux to the 
new species 7’. rotundidens, remarking that the only differ- 
ence from 7’. aquatilis consists in its slightly smaller dimen- 
sions. This distinction does not appear of specific value. 
Filhol (Ann. Sci. Géol. vol. viii. art. 1, p. 302) records 
the present species from Caylux. Purchased, 1884. 
Specimens provisionally referred to the present Species. 
Schlosser? and Filhol® refer the species of Theridomys from the 
Upper Eocene of Vaucluse to 7’. sederolithicus, Pictet (7. vaillante, 
P. Gervais), and 7’. cuviert, Pomel; but the writer has not been able 
to distinguish the specimens from those deposits mentioned below 
from the present species. Seeing that 7’. aquatilis occurs in the 
phosphorites, there is no reason why it should not also occur in the 
Vaucluse beds. Schlosser is, indeed, inclined to identify the Vau- 
cluse 7’. cwviert with his 7’. rotundidens, which the present writer 
cannot distinguish from 7’. aquatilis. 
* Palezontographica, vol. xxxi. p. 58 (1884). 2 Ibid. 
3 Ann. Sci. Géol. vol. vii. art. 1, p. 320. | 

