28 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 79 i 



This petrel was first seen near Indefatigable Island June 21, dur- ; 

 ing some rough weather, and later was observed almost daily. It 

 seemed to frequent the open stretches more often than the Galapagos 

 shearwater, though at times the two species were found together. I 

 Only on a few occasions did they come near enough to the yacht to 

 be taken, and then only when it was impracticable to retrieve speci- , 

 mens. One evening when we were returning to anchorage from 

 Daphne Island several hundred were seen in a rather dense, hovering j 

 group near Eden Island, where evidently they were feeding among I 

 a large shoal of small fish. On July 7, while en route to Academy 

 Bay, Indefatigable Island, from Chatham Island, numbers were 

 continually seen, both flying and sitting on the surface of the water. 

 Numbers came within easy range and would have been taken had it j 

 been practicable to pick them up. Fortunately, through the kindness j 

 of Seaman LeMert Mills, two that flew aboard that night were saved ! 

 and made into specimens. 



The last one of these petrels was seen on August 30, several hun- 

 dred miles west of the Galapagos group. 



OCEANODROMA CASTRO CRYPTOLEUCURA (Ridgway) 



Hawaiian fork-tailed petrel 



Cymocliorea cryptoleucura Ridgway, Proc. U. S. Nat. Mus., vol. 4, March 29, 

 1882, p. 337. (Waimea, Kaui, Hawaiian Islands.) 



A male was secured at the Hood Island anchorage, Galapagos 

 Islands, July 11, 1929. 



Comparison of a small series of these petrels shows two races, one 

 for the Atlantic area and one for the Pacific, as indicated by 

 Mathews,-- of which the latter, bearing the name cryptoleucura, 

 ranges from the Galapagos to the Hawaiian Islands. It is distin- 

 guished from O. o. castro by somewhat more sooty coloration and 

 slightly smaller size. The male from Hood Island measures as 

 follows: Wing, 155.0; tail, 69.2; culmen from base, 15.0; tarsus, 

 21.2 mm. 



Although stormy petrels were in evidence daily, the specimen that 

 came aboard at Hood Island was the only one of this kind noted. 

 Without long field experience with these birds, it is very difficult, 

 except under unusually favorable conditions, to identify the species 

 until they come to hand. While they are rising and dipping over 

 the surface in unison with the motion of the waves, it is often im- 

 possible to see even such marked characters as the extended feet of 

 the Wilson type. It is more than probable that we saw Hydrohates 

 tethyfi, a Galapagos species, without recognizing it. 



==2 Syst. Av. Austr., pt. 1, June 13, 1927, p. 106. 



