BIRDS OF NORTH AND MIDDLE AMERICA. 481 



CAMARHYNCHUS AFFINIS Ridgway 

 ALLIED GROUND FINCH. 



Similar to C. j)slttacHlus, but smaller (the bill especially). 



J/ff/t.— Wing. 68.00-72.00; culmen, 12.50-13.50.^ 



Female f.—\N'mg, 65.53-69.85 (67.56); tail, 38.61-43.18 (40.89); cul- • 

 men, 14.48; g-on3^s, 7.37-7.62 (7.49); width of mandible at base, 7.62; 

 depth of bill at base, 10.16; tarsus, 20.32-22.86 (21.59); middle toe, 

 13.97.' 



Galapagos Archipelago (Albemarle and Narborough islands). 



CamnrJiyncJius affinity Ridgway, Proc. U. S. Nat. Mus., xvii, no. 1007, Xov. 15, 

 1894, 365 (Albemarle I., Galapagos Archipelago; collection of Dr. G. Baur"); 

 xix, 1897, 5o-l (monogr. ). 



Geospiza affinis Rothschild and Hartert, Xovit. Zool., vi, Aug., 1899, 168 (Albe- 

 marle and Xarborough islands). 



CAMARHYNCHUS COMPRESSIROSTRIS Ridgway. 

 THIN-BILLED GROUND FINCH. 



{Adult male unknown.) Adult female similar to that of C. pi<it- 

 taculus but smaller, with the bill nmch narrower, more compressed, 

 and with straighter culmen; basal width of mandible less than length 

 of gonys instead of greater, and basal depth of bill less than length of 

 maxilla from nostril; wing less than 66.04; culmen (from extreme 

 base), 15.24; basal depth of bill, 10.16. 



Adult female. — ^ Above light olive (less grayish than in C. psittaculuH., 

 more so than in C. incertus)^ the pileum obsoletely streaked and the 

 back spotted with darker; wings and tail dusky grayish brown, the 

 feathers with light butfy olive margins, the middle and greater wing- 

 coverts broadlj' tipped (the former sharpl}-) with pale brownish buff; 

 face and under parts very pale j^ellowish buff, tinged with pale olive- 

 brown on sides and flanks, where obsoletely streaked (broadly) with 

 grayish olive-brown; under wing-coverts white tinged with pale buff', 

 most stron-gly toward edge of wing; maxilla pale cinnamon-brown, 

 with terminal portion of culmen dusky; mandible paler, inclining to 

 brownish buff'; "'iris very dark brown;" legs and feet blackish brown; 

 length (skin), 107.95; wing, 65.28; tail (rectrices only partly grown 

 out); culmen, 15.24; gonys, 8.13; width of mandible at base, 7.37; 

 depth of bill at base, 10.16; tarsus, 22.86; middle toe, 15.24.* 



' Fide Rothschild and Hartert; the averages not given by them. 



' Two specimens, not sexed, from Albemarle Island. 



■*Type now in the Tring Museum. 



*Type, no. 471, Baurcoll. (Tring Museum ) , Jervis Island, Galapagos, Aug. 8, 1891. 



It is much to be regretted that Messrs. Rothschild and Hartert have not given 

 reasons for referring this bird to C. j)siiiMculus. having been content to place the name 

 in the synonymy of that form without explanation. The measurements certainly 



17024—01 31 



