LIFE HISTORIES OF NORTH AMERICAN PETRELS AND PELICANS. 147 



Pacific coast subspecies of Oceanodroma leucorhoa. It is a soutliern 

 bird ranging north to the southern boundary of California and 

 known to breed only on Guadalupe Island, Lower California, where 

 Mr. Anthony found it. Since that time Mr. AV. Otto Emerson 

 (1906) described two new species, Oceanodroma heali, smaller than 

 0. leucorhoa but larger than the others, breeding from the Aleutian 

 Islands to southern Ala.ska, and O. heldingi, smaller than heali and 

 decidedly grayer, breeding from Vancouver Island to northern 

 California; to O. kaedingi, the smallest of all, he attributed a still 

 more southern range. His species would thus show a gradation in 

 size from north to south which might be expected. According to 

 the ruling on which our check list was based O. heali and O. held- 

 ingi Avere not considered worthy of recognition, so the birds breed- 

 ing on the Alaska coasts were referred to O. leucorhoa., and all 

 those breeding on the Pacific coast of the United States were called 

 0. kaedingi. 



Kecent investigations have shown, however, that all of these 

 birds are only subspecifically distinct and that heldingi is a synonj'm 

 of heali. Eather than attempt to discuss the matter more fully 

 here I would refer the reader to what has been published on the 

 subject by Dr. H. C. Oberholser (1917), Dr. Joseph Grinnell (1918), 

 and Mr. Leverett M. Loomis (1918), three eminent authorities who 

 liave studied the question quite thoroughly. 



As we know very little about the distribution and practically 

 nothing about the habits of the Kaeding petrel, I shall not attempt to 

 write its life history. Probably it does not differ materially from 

 that of the Leach petrel. Mr, xVnthony wrote me that on Guadalupe 

 Island the Guadalupe petrel breeds early, April 20 or earlier, and 

 that after they are through breeding the Kaeding petrels use the 

 same burrows among the pines at the north of the island. 



DISTRIBUTION. 



Breeding range. — Known to breed only on Guadalupe Island off 

 the Pacific coast of Lower California. 



Range. — Pacific coast region of Lower California. Xorth to 

 extreme southern California (off San Diego). South to the Ke- 

 villagigedo Islands (Clarion and Socorro Islands), and at sea to 

 5° 30' North and 102° West. 



OCEANODROMA LEUCORHOA BEALI (Emerson). 

 SEAL PETREL. 



HABITS. 



When the next edition of our check list appears the above name 

 will probably replace the name of the Kaeding petrel, for reasons 



