NO. 1116. PROCEEDINGS OF THE NATIONAL MUSEUM. 649 



Specific characters. — Axillars and under wiug-coverts mostly white- 

 above, includiug hind part and sides of head and neck and upper tail- 

 coverts, dark browuish slate, darker on wings and tail, nearly black on 

 head; feathers of neck and upper tail-coverts (the latter very abruptly) 

 white beneath the surface; forehead, lores, cheeks, and entire under 

 parts white, the sides and longer under tail coverts sometimes irregu- 

 larly barred Avith dusky. Wing, ll.r)0-12.25; tail, 5.01-5.47; culmen, 

 1.20-1.30, from nasal tubes, 0.90-1; depth of maxilla at base, 0.55-0.70; 

 tarsus, 1.40-1.55; middle toe (without claw), 1.70-1.78. 



i^rt^z/e.— Galapagos Archipelago: Chatham Island (Kellett and 

 Wood); "off pass between Indefatigable and James" islands (Baur 

 and Adams); "between Barrington and Indefatigable'' islands (Baur 

 and Adams). Sandwich Islands??. 



TLe six examples of this species in Messrs. Baur and Adams' collec- 

 tion present among themselves some very noticeable though slight 

 variations of plumage, these variations occurring in birds of the same 

 sex and obtained the same date. In one female the back and scapulars 

 are nearly uniform, though the tips of the feathers (broadly) are more 

 of a grayish cast than the central (mostly concealed) portion ; but there 

 is not the slightest indication of the narrow grayish white tips seen to 

 a greater or less extent in all the others, these being particularly well 

 developed in another female, in which the whole dorsal region shows, 

 besides these narrow whitish tips, a distinct ashy wash. In four of the 

 six specimens the dusky color of the opposite sides of the lower neck is 

 well separated by the immaculate pure white of the chest and lower 

 fore neck; in one of the other two the dark color encroaches consider- 

 ably on the sides of the chest, and even the front portion of the latter 

 has a few very indistinct irregular transverse bars of grayish; while 

 in the lemaining example these markings are much more distinct, par- 

 taking of the character of quite regular bars, extending quite across 

 the median portion of the chest. There is also some variation in the 

 white on the basal portion of the inner webs of the primaries, which 

 in some specimens is more distinctly contrasted with the adjacent dusky 

 color than in others, but its extent is essentially the same in all. 



According to Mr. Salvin,^ my Aestrelata sandicichensi.s is the same as 

 A.pha'opygia. They certainly are much alike, and may be identical. 

 But I am unable to match the type of the former among the six exam- 

 ])les of the latter with which it has been carefully compared aiul from 

 all of which it differs in the following particulars: 



A. sandwichensis: Bill smaller (culmen from base of nasal tube 1.20, 

 from anterior end of same 0.00), and nasal tubes shorter (0.30) ; hind 

 neck and sides of neck light sooty slate, like back; feathers of back 

 and scapulars without paler tips; inner webs of primaries without any 

 definite white space, though basal portion is w^hitish. 



A. pluvopyyia : Bill larger (culmen from base of nasal tube 1.30- 



See Proc. U. S. Nat. Mus., XI, 1888, p. 104. 



