Distribution of Birds in North Biissia. 3 



that and 60° N. lat., or about the latitude of St. Petersburg, 

 but also including the whole of the Government of Vologda. 



Further, for purposes of comparison, I have divided the 

 " NoETHERN Division " into three Districts^ which I name 

 and define as follows : — • 



1st. " The N.W. District of the Northern Divisiony — In- 

 cluded between 30° and 40° E. long, (and north of 64" 30' N. 

 lat., which latter parallel passes through the Gulf of Onega). 

 This includes the whole of the Kola peninsula, and all west 

 of the White Sea up to the frontier of Russian Finland. By 

 reference to the list of authors given further on, it will be seen 

 that our materials for this district are far from complete [vide 

 also inf-h, page 4). 



2nd. " The North- Central District of the Northern Division.'''' 

 — Included between 40° and 50° E. long, (and north of 64° 30' 

 N. lat., but including the district immediately around Cholmo- 

 gory). This includes the delta of the river Dvina and the 

 country east of the White Sea as far as the watershed of the 

 Peza and Zylraa rivers (or the plateau of the Timanskai 

 Mountains), also the island of Kolguef in the Arctic Sea. 

 Our materials for this portion are fuller than for either of the 

 other two districts. 



3rd. " The NE. District of the Northern Division^ — In- 

 cluded between 50° and 65° E. long, (and N. of the parallel 

 of 64° 30' N. lat.). This includes the country from the head- 

 waters of the Zylma (or plateau of the Timanskai Moun- 

 tains) eastward, the valley of the Lower Petchora river to the 

 Ural Mountains ; and north-eastward to the Kara Sea and the 

 range of the Paechoi Mountains, and including the Island of 

 Waigats and adjoining seas*. 



In the second place, I have under each district entered the 

 records of the authors who have treated more or less of the 

 birds of the Northern Division ; and I now proceed to give 

 a list of these, with the titles of their papers, in chronological 

 order. The capital letters affixed to the notice of each indi- 

 cate the extent of each author's field-work, or the districts in 

 connexion with which he has written. I defer a criticism of 

 the doubtful records until towards the close of the paper, 

 merely indicating here the number of species recorded or added 

 to the fauna by each author. The numbers 1 to 17, pre- 

 ceding the following notices, are used for reference in the 

 Table further on. 



* I have similarly divided the southern division into three district?, 

 but I need not at present name or define them. 



1* 



