Vol. II, Pt. I] GIFFORD— BIRDS OF THE GALAPAGOS ISLANDS 23 



than in the other, although both were taken on July 27, 1905. 

 New proximal primaries are appearing in both, and in one, 

 new middle rectrices. In the other, the outer rectrices are ap- 

 pearing first. Undoubtedly this is the postnuptial moult, as 

 proved by the presence of a few large-sized young on the 

 nesting-site. 



The Clipperton Island adults, taken during the first half of 

 August, 1905, are all in somewhat fresher plumage; for the 

 breeding-season was not over, as it was at Oneal Rock. With 

 one exception, none show signs of feather-growth. In No. 

 1330 C. A. S., a few new interscapulars are appearing, their 

 bases being still enveloped in the sheath. 



Extreme and average measurements in millimeters are as 

 follows: Fifteen adult males— Wing 275-295 (285); tail 

 142-194 (168); culmen 40-44.5 (42.4); tarsus 20.6-22.9 

 (21.9) ; middle toe 17.5-21.5 (20). Twelve adult females- 

 Wing 278-300 (288); tail 170-216 (189); culmen 40-43 

 (41.2); tarsus 20.7-23 (21.6); middle toe 18.4-20.9 (19.6). 



The following lengths and extents in millimeters were 

 taken by Mr. Beck from birds in the flesh. The lengths of 

 four males were 390, 450, 455, and 465 ; the extents were 838, 

 880, 882, and 899. A female measured 460 in length, and 870 

 in extent. 



The following remarks are based entirely upon the series 

 of fresh eggs collected on Clipperton Island, August 10, 1905. 



They vary a great deal in shape, the majority being ovate, 

 elliptical-ovate, and elongate-ovate. The rarer shapes are 

 short-ovate, cylindrical-ovate, oval, elliptical-oval, and nearly 

 ovate pyriform. 



The ground color is likewise subject to great variation. 

 The majority of the eggs vary in this regard from white to 

 cream-color, cream-buff, and pinkish buff. In a number of 

 cases the white ground color has a slight bluish cast. One 

 abnormally-colored egg has a vinaceous-cinnamon ground with 

 cinnamon-rufous spots and blotches, and suffused dull purplish 

 blotches which appear to be beneath the surface. Another is 

 vinaceous-buff, with bay spots of varying size and the usual 

 faint suffused blotches. Still another is pale vinaceous-buff, 

 almost immaculate save for several dark brown spots at the 

 larger end, and a few pale suffusions. All of the eggs of the 



