144 Paf>ers from flic Marine Biological Laboratory at Tortugas. 



individuals), Bryant, as has been before remarked, appears to be the only 

 naturalist who has recorded an authentic description of its nesting in this 

 region. The booby's claim to breeding within the limits of the United 

 States rests on Audubon's account^ of its nesting on " Noddy Island " in 

 the Tortugas, where, in May, he found that " most of the birds were sitting " 

 on " large and flat " nests " formed of a few dry sticks, covered and matted 

 with sea-weeds in great quantity " and placed " on the top of a bush," while 

 the down-covered nestling is said to have had " the bill and feet of a deep, 

 livid blue or indigo color." But other writers are agreed that Snla leuco- 

 gastra begins to nest in this region in February, lays usually two eggs 

 (always on the ground), uses little if any nesting material, and the bill and 

 feet of the nestling are yellowish-green. 



Bryant (/. c), who has commented on this discrepancy, thinks that 

 Audubon may have mistaken nests of the brown pelican for those of the 

 booby ; but Audubon's familiarity with the pelican's nesting habits, together 

 with his statement that in all the "booby's" nests examined only one egg was 

 found, some of which had the " chick nearly ready for exclusion," renders 

 Bryant's hypothesis improbable. Furthermore, Audubon's detailed state- 

 ment that there was a " constant succession of birds coming in from the 

 sea with food for their young, consisting chiefly of flying-fish and mullets, 

 which they disgorged in a half-macerated state into the open throats of their 

 offspring," shows, in spite of some looseness in the description of the manner 

 of feeding, that he had abundant opportunity to observe the parents at close 

 range. That his bird was not Siila Icncogastra there can be small room for 

 doubt, but it is bv no means so certain that it was not the red-footed booby 

 {Siila piscator), a species which has been found nesting in Cayman Brae, 

 South of Cuba," and which nests in bushes and lays but one egg. 



It is true that Audubon both describes and figures Sula Icncogastra ; 

 nevertheless he observes " that none of the birds which were still brown 

 had nests, and that they roosted apart, particularly on Booby Island (a 

 sand-bar), about 8 miles to the northeast of the Tortugas Lighthouse," which 

 he had found to be " covered with boobies." 



This view of the case finds support in the fact that the collection of the 

 Philadelphia Academy of Natural Sciences contains a specimen of Sula 

 piscafor collected by Audubon in Florida and labeled by him "Sula fusca," 

 under which name Sula Icncogastra was known to him. It is evident, there- 

 fore, that Audubon confused the two species, an error which may account 

 for his figuring and describing Snla Icncogastra when writing of the nesting 

 habits of what appears to have been Snla piscator. 



' Orn, Biog., ni, pp. 63-77. 



" Maynard, Cont. to Science, i. pp. 40-48, 51-57. 



