Vor. II, Pr. IT] LOOMIS—A REVIEW OF THE TUBINARES 153 
were no flocks, however, not more than two or three being 
seen together. On all occasions these petrels were silent, even 
when following the schooner and picking up turtle fat in com- 
pany with Dark-rumped Petrels. Their flight was butterfly- 
like, and more erratic than the flight of the Graceful Petrels. 
Galapagos Short-eared Owls are their great enemies on land, 
the remains of the petrels being often found in owl pellets. In 
life the bill, orbital ring, and feet are black and the irises dark 
brown. 
Mr. Beck’s label states that the egg, mentioned above, was 
found in a slight hollow in the soil under a lava block on the 
south side of Tower Island and that the nesting season had 
passed, although two or three hundred Galapagos Petrels were 
seen flying about over the nesting ground. He affirms that the 
identity of the egg is “sure.’’ Nevertheless, a petrel ege taken 
without the parent bird is not above suspicion. The egg is 
cvate in form, inclining to elliptical ovate, and white, with a 
very few minute dark dots, so small and scattered as to be 
hardly perceptible. It measures 26.7 x 19.9 mm. So far as I 
am aware, no description of the egg of this species has ap- 
peared in the literature. 
The ninety-two Expedition specimens of the Galapagos 
Petrel have the tail emarginated,* very much as in Oceano- 
droma castro. Many of the specimens have the tarsus de- 
cidedly longer than the middle toe and claw, which is like- 
wise true in numerous specimens of Oceanodroma melania, 
these relative dimensions being unstable in the Thalassi- 
drominze—see tables of measurements under the different 
species. The usual point-of-wing-formula in the Galapagos 
Petrel and in O. melania is: primary 2>3>1>4. Obviously, the 
Galapagos Petrel is not a square-tailed, but a fork-tailed storm 
petrel. It is therefore transferred from the genus Thalassi- 
droma to the genus Oceanodroma, the technical name of the 
species by this association becoming Oceanodroma tethys. 
The tone of the brown of the greater wing-coverts varies 
considerably, being very pale in some specimens, and the lateral 
1In his description of the species Mr. Salvin states that the tail is “slightly forked” 
(mon., p. 346), but in his key to the genera he states that the tail is ‘‘not distinctly 
forked” (p. 343). 
