Report of a Mission to Guam. . 23 



7. PuflBinus tenebrosus Pelz. Pel^eln's Shearwater. 



Upper color soot}' black, sides of neck and breast slaty with 

 whitish margins to the feathers. Length 12, wing 7.20-7.80, tail 

 2.95-3.25, culmen 1-1.05, tarsus i. 40-1 .45, mid-toe and claw 1.50- 

 1.60. Hab. Coast of Australia. 



8. Puffinus obscurus Gm. Dusky Petrel. 



Probabh' same as above. Length 12, wing 7.8, tail 3.2, bill 

 1.5, tarsus 1.5, mid-toe and claw 1.6 (Samoan Islands). Hab. 

 Tropical and sub-tropical seas. 



Order STEGANOPODES.— Totipalmated Swimmers. 



a'. Nostrils distinct, bill sharp-pointed without hook, chin 

 feathered, tail short, gradviated, in the adults the two middle 

 feathers are greatly elongated. Family Phaethontidcs . 



a-. Nostrils not distinct, head partly naked, bill stout but not 

 hooked, tail about half as long as wing. Family Sididcc . 



SL^. Nostrils distinct, bill hooked at tip, lores feathered, upper 

 plumage black, tail forked, wing long. Family Fregatida: . 



Family PHABTHONTID^.— Tropic Birds. 



Genus PHAETHON Linn^us. 



9. Phaethon candidus Temm. Boatswain Bird. Tropic 



Bird. 



General color pure white ; a black band bordering both sid^s 

 of the head, passes through the eye, and terminates in a crescent- 

 shaped mark at gap ; a black band on the wings. Length 30, cul- 

 men 1.8-2, wing 10-10.6, tail 17. 3-21, tarsus .8-. 9. The young 

 are barred with black. Hab. Inter-tropical seas, except coast of 

 North America. "Resident on Agrigan, of the Marianas." 



Family SUI/ID^.— Gannets. 

 Gknus SUI/A Brisson. 



a'. Feet greenish or 3'ellowish ; head, breast, neck and upper 

 parts brown. Siila sula. 



a-. Feet always reddish, head and neck white, tinged with 

 buff ; general color white. Sjila piscator. 



