Bibliographical Notices. 



51 



IV. Mackopoda. Artus distincte saltatorii, anteriores brevissimi, 

 230steriores longissimi ; Cauda longa pilosa ; foramen infraorbi- 

 tale magnum. 



The four genera belonging here are divided into two sections. 



a. Dentes raolares irregulariter incisi. 



Dlpus ; Scirtites, mihi (Alactaga, Fr. Cuv.) ; Jaculus, Wagl. 



b. Dentes molares ab uno latere partiti. (Meriones, F. Cuv.) Pe- 

 detes. 



Geog. distrib. Over Asia and a small part of European Russia, 

 Africa, Northern America, and one occurs on New Holland. 



V. Chinchillina. Auriculae magnse ; scelides antipedibus subduplo 



longiores ; cauda producta, supra et ad apicem longius setosa ; 

 vellus molle ; dentes molares ^ e laminis 9-3 parallelis com- 

 positi. 

 Three genera : Eriomys {Chinchilla), Lagidium (Lagotis), Lago- 

 stomus. 



Geog. distrib. South America. 



VI. PsAMMORYCTiNA. Habitus murinus, artus proportionales, au- 

 riculcE mediocres (rarius magnse), foramen infraorbitale magnum, 

 mandibulas angidus in cusj)idem elongatum excurrens, dentes 



molares f . 



Hahrocoma. 



Octodon. 



Psammoryctes. 



ft- 



Capromys. 

 Aidacodus. 

 Loncheres. 



(Nelomys and Echimys.) 

 Cercomys. 

 Dactylomys. 

 Petromys. 

 Confined principally to South America. 



VII. CuNicuLARiA. Corpus crassum, cylindraceura, caput obtusum, 

 oculi minuti aut tecti, auricula et cauda nullse aut parvse, artus 

 anteriores posterioribus robustiores, pedes 5-dactyli, dentes pri- 

 mores exserti, lati, truncati. 



Ungues anteriores breves 



Ommatostergus . 



Sped ax. 



Chtonoergus. 



Rhizomys. 



Georhycus. 



Ctenomys. 



Geog. distrib. 

 rica. 



VIII. MURINA. 



ft. Ungues anteriores longissimi. 

 Siphneits. 

 Ascomys. 

 Thomomys. 

 Geornys. 

 Bathyergus. 

 Haplodon {Aplodontia, 

 Richardson) . 

 South-eastern Europe, Asia, Africa and Ame- 



Oculi distincti, auricula et cauda plus minusve 

 exserta}, artus posteriores anterioribus longiores, pedes ante- 

 riores digitis 4 et verruca hallucari, posteriores 5-dactyli, cauda 

 nuda aut minus pilosa ; foramen infraorbitale longitudinale, 

 E 2 



