160 CALIFORNIA ACADEMY OF SCIENCES  {Proc. 41H Ser. 
Oceanodroma leucorhoa (Viecillot): LEACH’s PETREL 
Covrs—Cymochorea leucorrhoa, I, 76, 90. 
SaLvin—Oceanodroma leucorrhoa, 347, 348; (?) Oceanodroma socor- 
roensis, 352; (?) Oceanodroma monorhis, 347, 356, pl. 2. 
GopMAN—Oceanodroma leucorrhoa, xxxv, 8, pl. 4; Oceanodroma 
beali, xxxv, 11; Oceanodroma beldingi, xxxv, 12; (?) Oceano- 
droma A iihen xxxv, 13; (?) Oceanodroma monorhis, xxxvi, 
S25 ol. .9! 
Enlargement of the synonymy of Oceanodroma leucorhoa 
has been in vogue of late years. Individual variation and geo- 
graphic variation in size have been given binomial names and 
treated as species. In order to elucidate these matters I have 
assembled for comparison a series of one hundred and seventy- 
one specimens ; thirteen from Bird Rock, Gulf of St. Lawrence, 
one from off Cape Verde, Africa, ten from Sitka Bay, Alaska, 
including the types of Oceanodroma. beali Emerson, six from 
the coast of Oregon, including the type of Oceanodroma 
beldingi Emerson, eight from Humboldt County, California, 
six from Southeast Farallon Island, one from Pigeon Point, 
California, the type and twenty-seven paratypes of Oceano- 
droma kaedingi Anthony, seventy-seven Oceanodroma socor- 
roensis C. H. Townsend, mainly from Los Coronados and San 
Benito islands, Lower California, and twenty-one Expedition 
specimens taken at sea south of the Galapagos Islands and dur- 
ing the return voyage. 
In considering color values in fuliginous storm petrels, it 
should always be kept in mind that the plumage in life soon 
loses its bloom and browns with wear, and that museum speci- 
mens fade with time, becoming valueless so far as nice distinc- 
tions of color are concerned. 
The tables of measurements, given beyond, prove that the 
minimum dimensions of the Bird Rock specimens are com- 
pletely overlapped by the maximum dimensions of the Sitka 
Bay specimens. In consequence the only character advanced 
in support of “O. beali” fails, the Alaskan bird not being “of 
uniformly smaller size” than the Atlantic one. 
“O. beldingi” is described as similar to “O. beali,’” “but de- 
cidedly grayer, and averaging notably smaller in length of 
wing and tail.” Seven July specimens from Oregon and Hum- 
boldt County, California, are not grayer than the types of “O. 
