166 BULLETIN 107, UNITED STATES NATIONAL MUSEUM. 
flock in a small tidal pool beside a grounded iceberg between Lyttleton Island 
and Cape Hatherton, and Mr. MacMillan heard them whistling off Sunrise 
Point. Returning from Cape Sabine to Cairn Point in mid-February, 1914, I 
saw many guillemots in the open water along the edge of the young ice... Or 
March 1, 1914, Doctor Hunt, the surgeon of our party, shot 19, all in winter 
plumage, in open leads off the mouth of Foulke Fjord, where many flocks of 
them were feeding. 
The fall migration of this species is not very extensive, so far 
as it is known, for it can be driven from its summer home only when 
the ocean is solidly frozen. Probably most of the Greenland birds 
are forced out to winter on the open ocean or around the edges of 
the ice packs. The birds which breed north of Hudson Bay prob- 
ably do not migrate through Hudson Strait, but winter in the south- 
ern part of Hudson Bay or in James Bay, which is almost always 
more or less open; the occasional freezing of this bay may account 
for the accidental occurrence of this species in Ontario. Mandt’s 
guillemot winters in Bering Strait, but does not seem to wander south 
of Norton Sound, Alaska. 
Cepphus mandti will probably prove to be a subspecies of Cepphus 
grylle. Numerous specimens of intermediate birds are to be found. 
in collections, which are either intergrades or hybrids. Two summer 
birds from the Gulf of St. Lawrence, which I have seen, show the 
intermediate characters. 
DISTRIBUTION. 
Breeding range.—Coasts and islands of the Arctic Ocean. From 
northern Greenland (Cape Union, Thank God Harbor, Bessells Bay, 
and Cape Lieber south to about Disco Bay), Spitzbergen, Franz 
Josef Land, Nova Zembla, the northern Siberian coast to Herald 
and Wrangel Islands, the vicinity of Point Barrow, Alaska, and 
islands north of Hudson Bay. South along the west coast of Ungava 
into James Bay. Birds have been recorded as far north as latitude 
84°. Nonbreeding birds may occasionally be found in Bering Sea 
and on the coast of Labrador (Cape Whittle, June 24), but breeding 
records from these localities need confirmation. Has been taken at 
Gaspe, Quebec, June 10. 
Winter range—As far north as open water can be found, south 
to Bering Strait (rarely Norton Sound) and Hudson Strait. Many 
doubtless winter in Hudson Bay and James Bay, occasionally reach- 
ing Lake Ontario, and some probably occur on the Labrador bones 
at this season. 
Spring migration Arrive in northern Greenland; Bowdoin Bay, 
May 8 (not common until late June) ; Thank God Harbor, February 
28 and during March; Cape Sabine, first seen March 15; northeastern 
Greenland, latitude 80° 10’, June 10. 
Fall migration—In northern Greenland last seen at Floeberg 
Beach, latitude 82° 27’, August 29; at Port Foulke, September 1; 
