the Birds of the Lower Petchora. 123 
giving place to the next species. We got it first at Ust Zyl- 
ma on the 23rd May, and continued to shoot numbers of them 
up to the time of our leaving that locality. But though plen- 
tiful at Ust Zylma, northwards we found them much rarer, 
only occurring here and there in pairs in the opens and 
clearings near the villages as far as Abramoff, or to about 20 
miles within the arctic circle. North of that locality we did 
not again see it. The northern range of this species appears 
to overlap the southern range of the next species during the 
breeding-season, and vice versd. Along the banks of the 
Petchora stray pairs, as already noted, occur to the north of 
the arctic circle; and only stray pairs of the Yellow-headed 
Wagtail occur to the south of the same degree of latitude. 
A considerable belt of country lying along the arctic circle, 
and for some distance north and south of it, may be looked 
upon as a neutral territory of the two species, where neither 
seems to have gained a firm footing. To the north of this 
belt the Yellow-headed Wagtail becomes the commonest bird 
of the delta; and to the south of the same belt the present 
species is abundant. 
Bupytes crtReouvs (Pall.). 
We did not find the Yellow-headed Wagtail at all at Ust 
Zylma; and only one small party, of five birds, was seen at 
Habariki, on the 38rd June, when a single example was shot. 
We again met with a pair on the Yorsa river, of which we 
shot the male, and we found them sparingly here and there 
in pairs, as already stated, frequenting the opener parts of the ~ 
woods, as far as Abramoff. After leaving Viski we found 
them more numerously. At Kuya they were common, and 
at Alexievka they were daily seen in abundance ; indeed this 
species appeared to be quite the commonest bird on the islands. 
It was present also, but not in such numbers, on the tundra. 
At Stanavoialachta comparatively few were met with; and 
none were seen at Dvoinik. The first eggs were brought to 
us by the Zyriani at Alexievka on the 19th June, the day of 
our arrival at that place; and we continued to get eggs ina 
fresh state for some time. We procured the young able to 
fly on the 20th July. 

