42 THE CONDOR Vol. XXII 
without encountering a burrow, and there were often five or six nests to the square 
foot. 
The vast majority were Oceanodroma leucorhoa beali, and the rule at this date 
was eggs on the point of hatching, although there were many young in all stages up to 
two-thirds grown. I noted one nest with the bird incubating two pipped eggs, and there 
was no other nest nearby from which an egg might have rolled. One Oceanodroma fur- 
cata was discovered on a fresh egg, and three young of this species, ranging from half 
to fully grown, were found. The adult was in a separate pocket of the same burrow 
with a brooding beali. The latter form prefers the softest ground, while the former 
seemed to select the edges of banks where small stones are mixed with the dirt, or the 
interstices in a pile of loose stones. As I am rather familiar with Oceanodroma socor- 
roensis during the nesting season, it may be of interest to compare some of its habits 
with those of beali. 
The Socorro Petrel begins laying on the Coronados Islands during the middle of 
June or a trifle later, while beali must start not later than the first week of that month, 
and probably before. The climate of Crescent City, even in mid-summer, is very cold and 
foggy, while that of the Coronados is warm and bright. Hence, I would expect at least 
three weeks difference in nesting dates, but in the opposite order, and for lack of a 
more plausible explanation, we may attribute the actual state of affairs to food condi- 
tions. 
Hach species occupies only burrows which the birds themselves construct. Those 
of the Socorros are about two feet long, while the average length of the Beals is sev- 
enteen inches—a difference which may be blamed upon the crowded quarters of the lat- 
ter. This form employs about twice the amount of weed stems for nest building as does 
socorroensis, and this is possibly due to the difference in climate. Beali is much more 
prone to eject oil than is the southern species, but none of the fwrcata which I secured 
showed any tendency to indulge in such tactics. In flight, the wing beats of beali are 
quicker; and I think that one who is familiar with both forms would have no trouble 
in distinguishing them apart while on the wing, if they be seen together. The main 
item of food of the Socorros is supposed to be larval rock lobsters, and this probably 
accounts for the fact that the deposit of fat on them is a pronounced red, almost the 
color of a brick, while beali feeds on other fare, and its fat is of the usual shade. 
In both colonies, almost every foot of suitable ground is occupied, but on the 
small island of the Coronados group where the Socorros are found, this is of very lim- 
ited extent, and the colony is crowded with but a few hundred pairs, while the north- 
ern island is almost ideal. There are no other birds, except a few guillemots, nesting 
upon this island to entice eggers; it is not far enough from the mainland to attract 
parties of all-day picknickers; and, for the same reason, cats are not likely to be intro- 
duced by campers. In fact, the only damaging influence seems to be a Barn Owl, which 
probably flies over from the mainland and raids the petrels every night, to which hun- 
dreds of wings scattered beneath the rocky points bear mute witness.—A. B. Howe zt, 
Pasadena, California, November 10, 1919. 
Further Colorado Notes.—In the last number. of Bird-Lore, Dr. Bergtold mentions 
the recent extension of the summer range of the Lewis Woodpecker (Asyndesmus lew- 
isi) eastward onto the plains in Colorado. It has formerly been considered a moun- 
tain bird in the summer time in this state, but we now hear of it frequently in the 
_breeding season far from the foothills. On June 28, 1917, I saw a pair with a nest ina 
telephone pole at Boone, far out on the plains, a long distance east of Pueblo. The same 
author also mentions the decrease in the number of English Sparrows in Denver. Their 
scarcity in portions of Boulder this year has been noted by people who do not ordi- 
_narily notice the birds very much. Whether it is only a temporary condition due to 
the exceptionally dry, hot summer, or to some other cause, I cannot hazard an opin- 
ion. Possibly the decrease has been going on for several years but has just attracted 
attention. We do not regret it. 
Dr. Bergtold also mentions the disappearance of Bullock Orioles from Denver early 
in August and their reappearance later in the month for a few days before their final 
disappearance for the winter. He suggests that perhaps the summer birds leave early 
