500 RESULTS AND CONCLUSIONS 



migrants. If we consider the European forms as the 

 typical ones, then the Siberian birds are Arctic forms. 

 It may be interesting to enumerate some of these. 



The Siberian form of the three-toed woodpecker, 

 which Bonaparte (adopting a manuscript name given it 

 by Brandt) called Picus crissoleucus, has the under parts 

 almost snowy-white, whereas the European form has the 

 feathers of most of the under parts conspicuously striated 

 with black. Some of the Siberian examples, probably 

 young birds, show some of these striations. 



The Siberian form of the lesser spotted woodpecker, 

 to which Pallas gave the name of Picus pipra, has the 

 whole of the under parts unspotted silky-white, with 

 the exception of the under tail-coverts, which are very 

 slightly streaked with black. The transverse bars on 

 the back and rump are also nearly obsolete. It is larger 

 than the South European form, the wing measuring 

 3.75 inches, and the tail 2.5. I have shot it at Archangel 

 and in the valley of the Petchora, and in addition to 

 •skins from the valley of the Yenesei, I have examples 

 from Lake Baikal, the Amur, and the islands of Sakhalin 

 and Yezo. Specimens from Norway and Sweden are, 

 however, somewhat intermediate, being as large as the 

 Siberian form, but in the colour and markings of the 

 back and under parts they are only very slightly paler 

 than the South European form. 



The Siberian forms of the Lapp tit, to which Cabanis 

 gave the name of Parus obtectus, are much less rusty 

 on the flanks than Norwegian examples. It is, however, 

 easy to find a complete series from the Scandinavian 

 bird, through Archangel and Petchora skins, to the 

 extreme Siberian form. 



The Siberian form of the marsh tit, to which 

 Bonaparte gave the name of Parus camtchatkensis, is an 



