494 Mr. O. Thomas on small Mammals 



and more heavily tufted tail, and its larger bullae. Comment 

 has already been made on the number of species, superficially 

 resembliiij^ eacii other, which live in tiiis region, and the 

 occurrence of these two closely allied Pericotes in the same 

 locality is very remarkable. But it has a parallel in Europe, 

 in the relationsiiip to each other of Apodemus sylvaticua and 

 A. fiavicollis. 



These latter, however, are inclined to segregate themselves 

 from each other locally, and it is not improbable that a closer 

 study of the actual places where the two Pericotes are found 

 will similarly show that they also are not both to bs caught 

 absolutely on the same ground. 



7. Graomys cachinus, Allen. 



(?. 321, 323,350, 378. 



[In naming these specimens T have re-examined the nn- 

 determined series referred to in my Chumbiciia paper, which 

 series I then supposed to belong to but a single species. 



To my surprise I now find that those specimens belong to 

 no less than three species — large, middle, and small, — distin- 

 guishable almost entirely by size, though, as is not unusual 

 in such cases, the development of ears, tail, and tail-tufts are 

 in proportion to the general size, the larger species being 

 finer animals throughout, with more handsomely tufted tails. 

 There are no specimens of a size to make determination 

 difficult, and the series of each of the three species contains 

 examples with fully worn teeth. The largest species, G. ca- 

 cJiinus, has a skull-length of 33*5-35 mm. Following this 

 we have 



Graomys medius, sp. n. 



Size less than in G. cachinns^ greater than in tlie next 

 species. Colour about as in cachinus^ but there is rather less 

 development of the buffy band along the sides. Under 

 surface white, the hairs either wholly white or slaty at base, 

 this character proving to be absolutely variable in all these 

 species of Graomys. Tail rather shorter and less tufted than 

 in cachinus. 



Skull in all waj's less developed than in cachinus, smaller, 

 with shorter nasals, supraorbital edges sharply angular, but 

 with less distinct beads than in cachinus ; bullse smaller. 



Dimensions of the type : — 



Head and body 124 mm. ; tail 150; hind foot 27 ; 

 ear 25. 



