470 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 56. 



next to be described, takes its place to some extent. In going north, 

 tbe nehouxi ttrs first seen in any numbers at Lobos de Afuera, where 

 the diminution in abundance of Sula variegata was first detected. 



An account of Sula variegata in the Galapagos Islands is given by 

 Snodgrass and Heller,^ but their observations regarding the habits 

 of this bird are at variance with mine. They say: 



No nest is constructed and generally only one egg is laid by each female. On Cul- 

 pepper Island we saw some nests containing two. They snap their beaks viciously 

 at the foot or leg of the intruding person, and a nesting bird can not be forced to leave 

 her egg. 



They observed the nests apparently only upon the level ground. 

 The measurements which they give, however, are far too large for 

 those of Sula variegata. Every measurement given in their table on 

 page 245 is from 10 to 20 per cent too large for variegata if the measure- 

 ments of my specimens taken in the type region are correct. They 

 also state that the bill is "light orange-red, yellowish at the tip and 

 along the commissure," which does not conform to the original 

 description of the species. Sula (Dysporus) variegata was described 

 by von Tschudi from the coast of Peru (Ornithologie, p. 313), 

 and, whUe his description is not given in great detail, it is unlikely 

 that my specimens were far from being typical. It seems possible, 

 therefore, that their identification was incorrect. Sula variegata has 

 a bluish horny colored bill, nests in Peru now chiefly in rough or 

 precipitous places, and has from 1 to 5 eggs for each nest. The adults 

 are not relatively noisy and desert the nests readily when approached. 



It may be noted that the specimens from which the measurements 

 of Snodgrass and HeUer were made were fully as large as the speci- 

 mens of Sula nehouxi, although variegata is a much smaller bird. 

 Their observations of the color of nehouxi agree with mine. Their 

 statement that its breeding habits are different from those of both 

 S. variegata and S. piscatrix wehsteri in that it invariably nests on 

 cliffs would indicate a very striking difference of nesting habits 

 between the birds of the same species on the Galapagos Islands and 

 the Lobos de Tierra relatively. S. nehouxi, as related below, was 

 never observed nesting except on the more level ground. Nelson * 

 gives some account of nehouxi as observed on the Tres Marias Islands, 

 west coast of Mexico. Nelson writes: 



They were breeding abundantly on the beaches and on a low flat area that covers 

 a part of the former island (Isabel). They were most numerous on the open beach a 

 little above high-water mark, but dozens of them were seen with their eggs farther 

 back among the bushes [p. 31]. 



> Snodgrass, Robert Evans, and Heller, Edmund: Papers from the Hopkins-Stanford Galapagos Ex- 

 pedition, 189&-99. XIV. Birds. Proceedings Washington Academy of Sciences, vol. 5, pp. 231-372. 

 1904. 



» Nelson, E. W. General account of the islands with reports on mammals and birds. In: North Amer- 

 ican fauna. No. 14. Natural history of the Tres Marias Islands, Mexico. United States Biological Survey, 

 1899. pp. 1-97. 



