Mr. H. Seebohm on the Ornithology of Siberia. 325 
very wild and difficult to approach, and said that he had 
chased it for a couple of days before he succeeded in se¬ 
curing it. 
This specimen differs from Hume^s description in having 
no spots on the head. Only a few of the feathers on the nape 
have slight indications of spots, almost like gold dust, at the 
tips. The plate of this bird in ^ Lahore to Yarkand ^ (p. 244) 
is by no means a good one. The bar on the wing in my 
copy is coloured very pale blue, instead of pure white; and 
the conspicuous white feathers on the carpal joint are entirely 
concealed by the feathers of the breast. 
PicoiDES TRiDACTYLus (Linn.). 
Pious tridactyluSj Linn. Syst. Nat. i. p. 177 (1766). 
Apternus crissoleucus, Bonap. Consp. Vol. Zyg. p. 9 (1854), 
ex Brandt, MS. in Mus. Petrop. 
On my arrival at the wintering-place of the ^ Thames ^ on 
the Arctic circle, I found the Three-toed Woodpecker common 
in the pine-forests on both banks of the Koo-ray'-i-ka, and was 
assured by the sailors that it had frequently been seen there 
throughout the winter. I brought home seven skins of this 
bird, six of which are representative examples of the form P. 
crissoleucus (Bp.), in which the underparts are much whiter 
than usual, the feathers on the belly and under tail-coverts 
being very slightly barred with black, and the outside tail-fea¬ 
thers also displaying more wffiite than in the common form. 
The seventh skin agrees exactly with skins of the usual 
colour in my collection from the Petchora, iVrchangel, and 
Norway. It seems doubtful whether P. crissoleucus be an 
Eastern form of P. tridactylus, or merely a very old bird 
of the latter species. I may remark that in my series of 
skins the yellow on the head of the male is more developed in 
the paler-coloured birds than in those more profusely barred, 
favouring the idea that the difference is one of age. 
SiTTA EUROPiEA, Linn. 
Birds are very rare in the Siberian forests in winter. I 
have often silently threaded my way between the pines on 
snow-shoes for hours without hearing a note or seeing a fea¬ 
ther. Then, perhaps, I should suddenly find myself in the 
