abstracts: ornithology 175 



which Ijieeds in tho North Athuitic and North Pacific Ocean; Oceano- 

 droma leucorhon beali. Emerson, which breeds from southeastern Alaska 

 to the coast of northern Cahfornia; and Oceanodroma leucorhoa kaedingi 

 Anthony, which occurs off the Pacific coast of Lower Cahfornia, south 

 to the Revillagisedo Islands, western Mexico. Of these three forms 

 only the first and third aie cun-ently considered valid. Furthermore, 

 Oceanodroma leucorhoa kaedingi has hitherto been treated as a species, 

 whereas it is but a subspecies of Oceanodroma leucorhoa. H. C. O. 



ORNITHOLOCtY. — .4 neir .•<i(bsj)ccics of (!eothlyi)is behUngi. Harry 

 C. Oberholser. The Condor 19: 182-184. December 7, 1917. 

 A very distinct subspecies of the Belding yellow-throat is heie de- 

 scribed as Geothlypis beldingi goldmani, from San Ignacio, Lower Cali- 

 fornia. It differs from Geothlypis beldingi beldingi in its nuich duller 

 and less yellowish upper paits, whitish instead of yellowish area on the 

 crown behind the black mask, and more restricted yellow of lower sur- 

 face. Its breeding lange is confined to central Lower California, al- 

 though a single specimen indicates its winteiing in the Cape San Lucas 

 region. H. C. O. 



ORNITHOLOGY. — .4 remarkable martin roost in the city of Wash- 

 ington. Harry C. Oberholser. Bird-Lore 19:315-317. De- 

 cember 1, 1917. 

 Although late summer roosts of the purple martin are by no means 

 uncommon in the eastern Ignited States, there is apparently no record 

 of a martin roost in the District of Columbia prior to 1917. During 

 the latter pait of the summer of this year great num])ers of the purple 

 martin (Progne subis subis) gathered nightly in the INIall, along Fourth 

 Street, where they roosted in the trees along the street-car line. The 

 birds were first noted here on August 5 and continued nightly to resort 

 to this roost until September 9. The numljer of birds ranged from 

 about 2500 to about 12,000, but the usual number was between 7000 

 and 8000. They assembled daily about 25 or 30 minutes before sun- 

 set and we;e all at i-est in the trees by from 12 to 30 minutes after 

 sunset. Their evolutions during this period were of much interest. 

 During the martin occupation this roost regularly housed also l^etween 

 100 and 500 European stailings (Sturtius vulgaris vulgaris), from 1000 

 to 4000 purple grackles (Quiscalus quiscida quiscula); also, on a few 

 days, a number of bank swallows (Riparia riparia riparia) and rough- 

 winged swallows (Stelgidopteryx serripemiis serripennis) . H. C. 0. 



