Bulletin American Museum of Natural History. [Vol. XIX, 



hairs which are apically wholly black. Front half of the top of the 

 head rus.ty cinnamon, the posterior half rusty, strongly varied with 

 blackish; sides efface and neck clear gray; fore limbs lighter gray with 

 a faint buff y wash ; sides of shoulders suffused (mostly beneath the 

 surface) with pale rufous; thighs pale rufous, with the longer hairs 

 banded subapically with black and with long white tips, mixed with 

 a few wholly black-tipped hairs ; upper surface of hind feet deep rusty 

 yellow or orange, the edges and lower surface clothed with gray or 

 yellowish gray hairs; front and sides of nose, under side of head, 

 throat, breast, and inside of fore legs whitish, the base of the pelage 

 blackish plumbeous; rest of ventral surface washed rather strongly 

 with pale rufous; tail above at extreme base tinged with rusty, the 

 rest gray, with a faint tinge of rufous apically at the base of the hairs, 

 the sides with a narrow band of black and a broad fringe of pale yel- 

 lowish white; a broad (25-30 mm.) subapical band of black; tail be- 

 low with the central area pale brownish rusty, increasing in intensity 

 apically, with a broad subapical band of black and a yellowish white 

 fringe. 



Measurements (from flat skin, apparently much shrunken). Total 

 length, 350; tail vertebrae, 100; hind foot, 59. 



Skull. Large, equal in dimensions to large skulls of Citellus bar- 

 rowensis and C. parryi, but general form less broad anteriorly and 

 rostral portion more elongated, giving quite a different contour as 

 seen from above ; interorbital area and nasals narrower, breadth across 

 base of premaxillae one-eighth to one-seventh less; antorbital foramen 

 oval, very broad and depressed. Total length, 59; greatest zygomatic 

 breadth, 37 ; nasals, 22, terminating about evenly with the premaxillae; 

 width of nasals at base, 5, as against 6 to 7 in barrowensis and parryi, 



Citellus stonei is easily distinguished from C. eryihroglnteius 

 (and C. plesius if different) through its immensely larger size 

 and very different coloration; and also from C. osgoodi, C. 

 barrowensis and C. parryi J in coloration, as well as in cranial 

 characters, as above detailed. In coloration it bears very 

 little resemblance to either of the three species last mentioned, 

 though perhaps most approaching C. osgoodi in general fea- 

 tures. 



1 In the series of C. parryi collected by Mr. George Comer for this Museum in tlid 

 vicinity of Repulse Bay are several specimens that fulfil all the requirements of Rich- 

 ardson's Arctomys parryi, var. \, phaognatha, reputed to have been based on a speci- 

 men said to have been "also brought from Hudson's Bay, but the particular district 

 not mentioned" (Fauna Bor.-Amer., I, p. 161) and described as "characterized 

 chiefly [in comparison with parryi] by a well-defined deep, chestnut-coloured mark 

 under the eye." Two out of the Comer series of nine specimens are thus marked and 

 a third shows a trace of the same mark, which is apparently a feature of season or of 

 very high coloration. 



