92 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



stayed out all day shooting every bird he saw, and even at that never 

 got more than ten birds in a single day. 



Two species only, the yellow honey creeper and the ant shrike, ■were 

 even fairly common ; all other land birds were in such small numbers 

 that of several of them he saw but one or two individuals during his 

 stay on the island. 



Owing to the dense jungles that completely cover the island, it was very 

 hard to get about, and the birds were all in the high trees, so tlmt it is 

 very possible Mr. Brown did not procure all the species that occur there. 



In spite of the late date, June and July, at which the island was 

 visited, the birds are in excellent plumage, showing no signs of wear or 

 fading. In a wet, heavily forested island such as Gorgona, the plumage 

 of the birds appears to keep in fine condition up to the very time they 

 moult, in marked contrast to what happens in dry, hot, barren regions. 



The four species of land birds we describe as new are strongly charac- 

 tei'ized, and additional material might show that one or two of the others 

 also represent new island forms. The new booby is quite different from 

 either Sula leucogadra or Sula brewsteri, though somewhat intermediate 

 between them. We give it specific rank, because the only alternative 

 is to consitler S. leucogastra, S. brewsteri, S. nesiotes, and the new form 

 subspecies of one bird, wliich we are not quite prepared to do. 



We are under great obligations to Dr. Robert Ridgway, Avho, though 

 extremely busy at the time, compared many of the specimens with the 

 material in the United States National Museum, and also to Mr. E. W. 

 Iselson for comparing the boobies with typical specimens in the United 

 States Biological Survey Collection. 



All the measurements are in millimetres, and the colors are according to 

 Ridgway's nomenclature. 



SULIDAE. 



1. Sula nebouxi Milne Edwards. 



One inmiatiire ^, June 26. 



Earlier in the season this species breeds abimdantly on Gorgonilla, according 

 to information given Mr. Brown by the fishermen who visit the island. 



2. Sula etesiaca, sp. nov. 



Type. -ColL E. A. & 0. Bangs, No. 14,026, adult <?, Gorgona Island, June 29, 

 1904. 



Five specimens, adults ^ 9, June 29 to July 2, 1904. 

 M. C. Z., No. 40,280, atUilt 9, Gorgona Island, July 1, 1904. 

 Characters. — Size about as in Sula brewsteri Goss. Intermediate in color 

 and color-pattern between S. brewsteri and »S'. leucogastra; in the adult ^ of 



