114 BUT .T.F.TIN 99, UNITED STATES NATIONAL MUSEUM. 



Genus SACCOSTOMUS Peters. 



•. 



1846. Saccostomus Peters, Ber. Koniglich Akad. Berlin, 1846, p. 258. (S. 



campestris.) 

 1903. Eosaccomys Palmer, Science, new. ser., vol. 17, p. 873. (S. campestris.) 



The tlii^ee species of pouched rats of the genus Saccostomus known 

 from British East Africa are closely related to South African forms, 

 and doubtless will prove to be geographical races of some earlier 

 named species when the group is carefully monographed. 



For measurements of specimens of Saccostomus see page 115. 



SACCOSTOMUS MEARNSI Heller. 



Plate 32. 



1910. Saccostomus mcarnsi Heller, Smithsonian Misc. Coll., vol. 54 [No. 1924], 

 p. 3. February 28. (Changarawe, British East Africa; type in U. S. 

 Nat. Mus.) 



1910. Saccostomus mearnsi Roosevelt, African Game Trails, Amer. ed., p. 

 473; London ed., p. 485. 



Specimens. — Two, as follows: 

 British East Africa: Changamwe (Mearns). 

 Doctor Mearns records the "iris very dark brown, almost black; 

 toes flesh color." 



SACCOSTOMUS UMBRIVENTER MUIer. 



Plate 32. 



1910. Saccostomus umbriventer Miller, Smithsonian Misc. Coll., vol. 54 [No. 



1925], p. 1. February 28. (Njoro Osolali, Sotik, British East Africa; 



type in U. S. Nat. Mus.) 

 1910. Saccostomus umbriventer Roosevelt, African Game Trails, Amer. ed., pp. 



473, 479; London ed., pp. 485, 490. 



Specimens. — Eight, from localities as follows: 



British East Africa: Kabalolot Hill, Sotik, 1 (Heller); Njoro 

 Osolali, 3 (Loring); Southern Guaso Nyiro River, 1 (Heller); Telek 

 River, Sotik, 3 (Heller). 



SACCOSTOMUS ISIOLi« Heller. 



Plate 31. 



1912. Saccostomus isiolx Heller, Smithsonian Misc. Coll., vol. 59, No. 16, p. 14. 

 July 5. (Isiola River, Northern Guaso Nyiro, British East Africa; 

 type in U. S. Nat. Mus.) 



Specimens.-— Twenty-nine, from localities as follows: 

 British East Africa: Isiola River, 20 (Heller); Lower Nyuki, 

 Northern Guaso Nyiro, 1 (Heller) : Mayo River, Laikipia Plateau, I 

 (Heller); Turah Water, Northern Guaso Nyiro, 7 (Heller). 

 One female contained four embryos, another six, on July 1. 



