
934 RODENTIA. 
India. This and the next specimen are slightly larger 
than the type specimen (woodcut, fig. 31); but as they are 
otherwise precisely similar, they have been provisionally 
referred by the present writer, in the ‘ Paleontologia In- 
dica,’ ser. 10, vol. ii. p. 107, to the same species. The 
length of the space occupied by the three molars is 0,019. 
Cauiley Collection. Presented, 1842. 
Fig. 31. 



m.1. m.2. m. 3. 
Rhizomys sivalensis,—Part of the left ramus of the mandible; from the Siwaliks 
of the Punjab. Indian Museum, Calcutta, $. (From the ‘ Palzontologia 
Indica.’) 
15926. Part of the right ramus of the mandible, containing the 
second molar and the broken bases of the teeth on either 
side; from the Pliocene of the Siwalik Hills. 
Cautley Collection. Presented, 1842. 
15927. Fragment of the left ramus of the mandible, containing the 
first and second molars, in a more worn condition than in 
either of the preceding specimens; from the Pliocene of 
the Siwalik Hills. Cautley Collection. Presented, 1842. 
15927 a. Two molar teeth; from the Pliocene of the Siwalik Hills. 
Cautley Collection. Presented, 1842. 
Section HYSTRICOMORPHA. 
Family THERIDOMYID A. 
This family was established by Alston’ for the reception of the 
genera Theridomys, Archwomys, and Issiodoromys. Schlosser? con- 
siders that the first two genera, together with Protechinomys and 
Trechomys, are most nearly allied to the existing Octodontidw (Lon- 
cheres and Kchinomys); while he refers® sstodoromys and the allied 
Nesocerodon to the Caviide (Dolichotis). This arrangement has been 
adopted here. 
Dentition:—I. 5, 0. °s Pm. 4, M. 2. 
* Proc. Zool. Soc. 1876, p. 88. 
* Palzontographica, vol. xxxi. p. 83 (1884). 8 Ibid. p. 15. 

