24'6 EODENTIA. 



rently adult squirrel, undoubtedly of this species, which has the sides of the head and 

 neck, the shoulder and outer side of fore limb and the middle area of the thigh 

 covered with dark, oHve-grey, finely annulated hair, the surrounding parts being pale 

 red ; the upper surface of the head, back, and tail being deep ferruginous. The feet 

 are dark, blackish-red. The presence of annulated hair in this specimen serves to 

 connect the so-called S. siamensis with the uniformly rufous squirrels, and illustrates 

 the last traces of the annulation of youth disappearing at maturity. It is also 

 important to observe that the light rufous specimens have the ridges of the teeth 

 not ground down whereas in the dark chestnut forms the teeth show signs of 

 use by being worn smooth. The ears are alike in all the specimens. An examina- 

 tion of the skull of the Siam forms, originally regarded by Dr. Gray as distinct under 

 the name of S. splendidus, does not bring to light any character by which to separate 

 them ; but I regret I have not had the opportunity to examine the skull of S. 

 siamensis. 



In the Ley den Museum there are six squirrels belonging to the S. ferrugineus 

 or red type, exhibiting progressive stages of pelage. The first specimen of these is 

 evidently in a transition stage, as there is a fiush of red all over the body, especially 

 marked on the ventral surface and on the head and neck, but of a much lighter tint 

 than in the wholly red squirrels. The tail of this specimen is annulated in the 

 ordinary way, but at its base a change is beginning in the fur, and also towards 

 the end, but the extreme tip is wanting. In the second specimen, the upper 

 surface of the head and a broad area down the back are deep rusty-brown, tending 

 to black on the back, consequent on an intermixture of black grizzling — a fact of 

 considerable interest in view of S. bocourtii — while, at the same time, the tail is 

 coloured as in the uniformly rufous animals. The lateral aspect of the squirrel, 

 from the muzzle, all along the face, neck, shoulder, flanks and thighs, is a dark 

 grey, more or less grizzled with yellowish; the legs are the same colour, only 

 darker, except on the fore feet which are becoming red ; the chin, throat, and 

 the under surface of the neck are also similarly coloured, but the chest and belly 

 and the inside of the thighs are rich chestnut. In a third specimen, the grey of the 

 sides has almost disappeared, but sufiicient remains to connect it with the previous 

 one, and the black grizzling of the back is all but lost. In still another speci- 

 men there is only the faintest trace of grey on the upper part of the fore limb 

 and on the thigh, but on the side of the face it is more distinct. In this stage 

 it would constitute the S. splendidus, Gray. In the two others, we have Siam 

 squirrels wholly rich, ferruginous red, darker on the back, where there is a tendency 

 to become black ; this dark area still holding true to its first character, while the 

 sides never assume a dark tint and are concolorous with the belly and with the 

 Hmbs and head. 



These mature individuals stand in the Leyden Museum as S, cinnamomeus, 

 Temminck. 



Two examples, one from Rangoon and the other from Upper Burma, belong 

 to the variety with the white tip to the tail, described by Beynaud as iS, keraudrenii, 



