122 SOME ERRORS REGARDING 
atricapillus), on the authority of a Western naturalist; 
that given for the egg of the Western Rough-Legged 
Hawk (Archibuteo ferrugineus), on the authority of the 
late Dr. Heermann; that of the Pigeon Hawk (Falco 
columbarius), the grounds for which supposition were 
given in full; and that of the Violet-green Swallow 
(Hirundo thalassina), on the authority of the late Dr. 
Webb. 
Subsequent discoveries of well-authenticated eggs of all 
these birds, quite different from those figured, seem to 
show that in each instance there is an error in regard to 
their identity. 
The egg figured for that of the Goshawk is, possibly, & 
very faint specimen of a Red-tailed Hawk’s. The Swal- 
low’s egg may be that of Hirundo lunifrons, and that taken 
for the sie Hawk’s, that of a Cooper’s Hawk. The egg 
given by Dr. Heermann as that of the Western Rough-leg, 
cannot now be determined. It evidently is not what it 
was supposed to be. 
_ Without seeking to conceal the fact that four of the - 
eggs figured in the Oölogy, appear not to belong to the — 
places in which they are found, nor to wholly absolve — 
the writer from so much of the responsibility as belongs — 
to him, of having been led into errors by the mistakes 
of others, he may here state that in regard to the egg © 
of the Falco columbarius, it was given as such at the =. 
as with he full expression of grave doubts as to its 
authenticity. All the facts, all the contradictory evi- 
emer pre with all possible care, and to the reader 
iven all the data in the writer's power, to enable 
ment. n e traveller, o 
