BIRDS 



327 



brownish plumage. Four have bhick feathers on the back with an ad- 

 mixture of brownish feathers, /. t?., the individual feathers are either 

 purely black or brown. They are all moulting. Hence, it appears 

 that here, at least, in June a moult occurs in which the brownish- 

 black plumage is lost and the black acquired. We have one male in 

 Stage V with the bill black, another with the bill black above and 

 pale below, one in Stage III with the bill entirely pale. All of these 

 are moulting. Two males in Stage IV, having the bills mostly pale 

 but partly dusky above, are not moulting. 



63c. GEOSPIZA FORTIS PLATYRHYNCHA 

 Heller and Snodgrass. 



Geospisa fortis platyrhyncha Heller and Sn'Odgrass, The Condor, Vol. 



Ill, No. 3, May-June, p. 75, 1901 (Iguana Cove, Albemarle Island). 

 Geospiza platyrhyncha Ridgway, Bull. U. S. Nat. Mus., 50, Ft. i, p. 673, 



1901. 



Range. — Iguana Cove, Albemarle. 



This form is similar in size and proportions to G. fortis dtibia^ 

 but the bill averages considerably wider at the base, being twelve 

 millimeters or more in width. The variety intergrades through forms 

 at the southeastern part of Albemarle and at Elizabeth Bay with G. 

 fortis fortis at Tagus Cove. 



It was not common at Iguana Cove either in January, March or 

 June. We have three adult males taken in January and March in 

 black plumage having very large thick bills with curved culmens, and 

 two females, one adult taken in March, the other taken in December. 

 The latter has the bill yellowish below and was moulting. The 

 ovaries were enlarged, however, as if the bird was breeding. 



Type. — Adult male. No. 5150 Leland Stanford Junior University 

 Museum; Iguana Cove, Albemarle, Galapagos, June 7, 1899. 



MEASUREMENTS OF ADULT SPECIMENS OF GeOSptZa fo7'tis 



platyrhyncha . 



