OCT., 1915. MAMMALS FROM BRAZIL AND PERU OSGOOD 195 



their inferior surfaces.* Numerous less obvious peculiarities of the 

 skeleton of Kerodon rupestris appear on close comparison. 



The remaining species may be divided into three groups of sub- 

 generic rank, Cavia, Galea, and Caviella. Cavia has long been in use, 

 Galea (type G. musteloides) has been regarded as a synonym of Kerodon, 

 and Caviella has not heretofore received a name. Although Cavia has 

 frequently been regarded as genetically distinct from the species now 

 included in Galea, the fact that several of the characters of Cavia and 

 Galea are combined in Caviella strengthens the conclusion that the con- 

 ditions may best be expressed by one generic and three subgeneric 

 names. A synopsis of the entire group based on the most convenient 

 and obvious characters is as follows: 



Sternum narrow and rounded. Genus KERODON 



Species: Kerodon rupestris Maximilian 

 Sternum broad and flat. Genus CAVIA 



Orbital branch of maxillary continuous; incisors unpigmented. 

 Posterior enamel loop of middle cheekteeth decidedly larger 

 than anterior and deeply indented on its outer border. 



Subgenus CAVIA 



Species: Cavia porcellus Linnaeus, f C. aperea Erxleben, 

 C. aperea azarce Wagner, C. rufescens Lund, C. rufescens 

 guian& Thomas, C. rufescens pamparum Thomas, C. 

 rufescens Venezuela Allen, C. cuileri Bennett, C. atahual- 

 PCB Osgood. 



Enamel loops of middle cheekteeth approximately equal in 

 size and shape. Subgenus CAVIELLA 



Species : C. australis Geoff. & D'Orbigny, C. mcenas Thomas, 

 C. niata Thomas, C. niata pallidior Thomas. 



Orbital branch of maxillary broadly interrupted by lacrymals; 

 incisors pigmented. Subgenus GALEA 



Species : C. musteloides Meyen, C. boliviensis Waterhouse, 

 C. boliviensis leucoblephara Burmeister, C. boliviensis 

 littoralis Thomas, C. auceps Thomas, C. spixi Wagler, 

 C. palustris Thomas, C. wellsi sp. nov. 



* This character is shared with Cavia, but sharply distinguishes from Galea; no 

 skeleton of Caviella has been available, 

 t Domestic guinea pig; syn. C. cobaya. 



