Vol. II, Pt. I] GIFFORD— BIRDS OF THE GALAPAGOS ISLANDS 63 



walked along, jumping from rock to rock and keeping hunched 

 up all the time. Upon sighting its prey, it advanced slowly 

 and stealthily, keeping behind rocks as much as possible until 

 within striking distance, when suddenly its head shot forth 

 and the fish was caught. On another day in the same locality 

 I watched for fully ten minutes one trying to swallow a crab, 

 and then had to leave without witnessing the conclusion. 

 The crustacean was held crosswise in the bird's bill, and to 

 all appearances was too large to be swallowed. Nevertheless 

 the bird stood tenaciously in one spot, and made occasional 

 unsuccessful gulps. 



Enlargement of the sexual organs was noted in adults taken 

 on Hood Island in September, on Indefatigable and Seymour 

 in November, on Chatham in February, and on Abingdon in 

 September. The sexual organs of two birds taken at Iguana 

 Cove, Albemarle Island, on March 17 were small. 



The only occupied nest discovered was in a mangrove thicket 

 on a small islet at Sappho Cove, Chatham Island, February 

 10. It was about twenty-five feet from the outer edge of the 

 thicket, and perhaps four or five feet above high water. It 

 was composed of twigs, was not particularly bulky, and con- 

 tained three greenish eggs, pipped and ready to hatch. Both 

 of the adults were present and kept up a continual squawking 

 while the nest was being examined. One stayed on the nest, 

 except when approached very closely, when it would move 

 away two or three feet, darting its bill at us continually. 



On Narborough on April 18, I killed, with a stone, a young 

 one which was just able to fly and fish for itself. Immedi- 

 ately its parent flew towards it screaming and with crest up- 

 raised. A similar instance was observed two or three days 

 before at Banks Bay, Albemarle Island. 



The Academy's series of adults exhibits a dichromatism. 

 Three adult males from Chatham Island are of the pale phase, 

 one (No. 2166 C. A. S.) extremely pale; a fourth male (No. 

 2137 C. A. S.) is rather intermediate, as is the only female 

 from that island. A male (No. 2167 C. A. S.) from Banks 

 Bay, and a female (No. 2168 C. A. S.) from Indefatigable, 

 closely resemble the Chatham males. Throughout the series 

 of adults there is considerable variation in color, most of the 

 birds inclining to the dark extreme. From the Academy's 



