24 
QUARTERLY BULLETIN. 
was unquestionably the same bird, and its plumage remained 
unaltered. 
Another point still more curious is : Why are some families 
of birds effected, as a rule, more than others? Cases among the 
trhigillidcB^ TetraonidoB^ and AimtidcB^ are of comparatively fre- 
quent occurrence, while among such large families as the Sylm- 
colidae^ Tyrannidae, and Scolopacidae^ we hear of but occasional 
examples. I will not express an opinion as to the truth of 
this problem, but leave it for more experienced heads to ponder 
over. 
Another abnormal state (Melanism), in which our birds have 
been found, is of exceedingly rare occurrence, and but five spe- 
cies have been recorded on my list : — Turdus migratorius^ Colap- 
tes auratus^ Melanerpes erythrocephalus^ Ortyx Virginianus^ and TJria 
grylle. 
Doubtless many other examples of albinism, and perhaps a 
few cases of melanism may be added to this list. 
NOTES ON BIRDS FOUND BREEDING ON COBB’S ISLAND, YA. 
BETWEEN MAY 25th AND MAY 29th. 1875. 
BY H. B. BAILEY. 
During so short a visit to any place the birds noticed must 
necessarily be only a small proportion of those actually occur- 
ring. The following observations relate principally to those 
breeding on the above named and two adjacent islands. Cobb’s 
Island is situated off Cape Charles, Virginia, and is about seven 
miles long by half a mile wide and being little more than a sand 
bar, is well adapted as a breeding resort for the various species 
of Terns and Waders found there. The coast side of the island 
is a magnificent beach which gradually rises up to an elevation 
of about fifteen feet from sea level in the centre, on which there 
is a rank growth of grass, while on the other side a long marsh 
extends in some places as far as half or three quarters of a mile 
from the main island at low water, but is nearly overflowed at 
high tide. In addition to the species enumerated below there 
were large numbers of shore birds migrating north, and several 
sportsmen were enjoying such shooting as we never get on the 
