

MONOGRAPH OF THE GENUS SCIURUS. 331 



This species, which has been described for so many years, 

 has been invariably considered by authors as identical with 

 the northern grey squirrel. There are however so many marks 

 of difference in size, colour, and habits, that any naturalist 

 who has had an opportunity of comparing specimens, and of 

 witnessing their difference in habit, will feel himself justified 

 in regarding them as distinct species. 



The head is shorter and the space between the ears propor- 

 tionately broader, than those of the northern grey squirrel : 

 the nose also is sharper. The small anterior molar in the 

 upper jaw is permanent, and not deciduous, as I have invari- 

 ably found it in all the specimens I ever examined. It is 

 considerably larger than in the other species, and all my spe- 

 cimens, which give evidence of the animals having been more 

 than a year old, instead of having the small, thread-like, sin- 

 gle tooth, as in the northern species, have a distinct double 

 tooth with a double crown ; the other molars are not unlike 

 those of the other species in form, but are shorter and smaller; 

 the upper incisors are nearly a third shorter. The body is 

 shorter, less elegant in shape, and has not the appearance of 

 sprightliness and agility, for which the other species is so 

 eminently distinguished. The ears, which are nearly trian- 

 gular in shape, are so slightly clothed with hair internally, 

 that they may be said to be nearly naked ; externally they 

 are sparsely clothed with short woolly hair, which, however, 

 does not extend beyond the margins, as in the other species ; 

 the nails are shorter and less hooked ; the tail is shorter, and 

 does not present the broad distichous appearance of the other. 



DIMENSIONS. 



IN. LIN. 



Length of head and body 9 6 



Ditto of tail (vertebra) 7 4 



Ditto to point of hair 9 6 



Height of ear „ 6 



Palm to end of middle claw 1 3 



Heel to end of middle nail 2 6 



Length of fur on the back „ 5 



Breadth of tail with hairs extended 3 



Colour. — Teeth light orange colour ; nails brown, lighter 

 at the extremities ; whiskers black ; nose and cheeks, and 

 around the eyes, a slight tinge of rufous grey. The fur on the 

 back is, for three fourths of its length, dark plumbeous, then 

 a slight marking of black, edged with brown in some hairs 

 and black in others, giving it, on the whole upper surface, a 

 uniform dark ochreous colour. In a few specimens there is 

 an obscure line of lighter brown along the sides, where the 



