1906.] 



NATURAL SCIENCES OF PHILADELPHIA. 



185 



feathers of the lores. From Collocalia fuciphaga fuciphaga, which also 

 to some extent it superficially resembles, it may be distinguished by 

 its larger size and more brownish upper parts, as well as most trench- 

 antly by the light brown instead of pure white bases of the loral feathers. 

 From Collocalia fuciphaga elaphra, a subspecies hereinafter described,^ 

 with which it agrees in size, and which it more closely approaches in 

 the general color of the upper surface, it differs in being rather more 

 blackish and more uniform above, the rump not so appreciably paler 

 than the back; in having much darker lower surface; also, and most 

 decidedly, in having the bases of the feathers of the lores light brown. 

 This last character alone will separate it from all forms of the genus 

 excepting C. leucophaea and C. thespesia.^ 



Three specimens of this new species were collected by ilr. Charles 

 H. Townsend in 1899, during his recent Pacific cruise on the U. S. Fish 

 Commission steamer ''Albatross." One of these, the single specimen 

 from Tahiti, is rather more brownish above, and a little paler on the 

 crissum than the type, but is very different from C. leucophaea ; another, 

 from the Marquesas Islands, is more blackish above and slightly darker 

 below; but the old specimen in the collection of the Academy of 

 Natural Sciences of Philadelphia is practically identical with our type. 



Measurements of Collocalia ocista are as follows: 



Collocalia fuciphaga fuciphaga (Thunberg). 



Hirundo fuciphaga Thunberg, K. Vet. Akad. Nva Handl., XXXIII, 1812, 



p. 153, pi. 4 (Java). 

 Hirundo vanikorensis Quoy and Gaimard, Voy. Astrolabe, Zool., I, 1830, p. 



206, pi. XII, fig. 3 (Vanikoro Island, Santa Cruz Islands, Pacific Ocean). 



Postea, p. 188. 

 ' Postea, p. 195. 

 ' Type. 



