334 BARBOUR: ZOOGEOGRAPHY. 



This snake is not found upon Swan Island having been probably extermi- 

 nated there by either the early settlers or the cats which they brought. Named 

 for Dr. William A. Brooks, President of the Swan Island Commerical Company 

 who aided Mr. Nelson throughout his trip. 



Alsophis Tudii Cope. 



Cope, Proc. Acad. nat. sci. Phila., 1862, p. 74. Barbour, Bull. M. C. Z., 1904, 46, p. 60. Amer. nat. 

 1907, 40, p. 231. Ro.sEX, Lunds univ. arsskrift, 1911, 7, no. 5, p. 40. 



This Bahaman ground racer, so closely allied to A. angulifer of Cuba, has 

 been found so far onlj' upon the islands of Eleuthera, New Providence, Long 

 Island, and Green Cay. This erratic distribution suggests that it probably 

 exists undiscovered upon many others. Thanks to Mr. Witmer Stone I have 

 examined the type No. 3,472, Acad. nat. sci., Phila. of Cope's Diadophis rubescens; 

 it belongs to this species. 



Alsophis ruflventris (DtiMERiL et Bibron). 

 DuM^RiL et Bibron, Erp^t. g^n., 1854, 7, p. 668. 



Of the types of this species one was said to have come from Brazil, and the 

 other has no locality record. Garman refers specimens from St. Kitts, Saba, 

 and Nevis, to this species while Boulenger (Cat. snakes Brit, mus., 1894, 2, 

 p. 125) adds St. Eustatius to the list of locahties. He includes Alsophis cinereus 

 Garman and A. rijersmaei Cope, as synonyms. 



Alsophis cinereus Garman. 

 Garman, Proc. Amor, philos. soc, 1887, 24, p. 282. 



This form, which is closely related to A. rufiventris, but easily distinguished 

 by having twenty-one rows of scales instead of twenty-three is found upon the 

 islands of St. Bartholomew and Anguilla. The types are No. 6,139, M. C. Z. 



Alsophis rijgersmaei Cope. 

 Cope, Proc. Amer. philos. soc, 1869, 11, p. 154. 



Cope says, "So far as yet known, this distinct species is confined to the small 

 island of St. Martins." There are no specimens in the collection here, so that 

 I can not verify Boulenger's placement of this species as a synonym of A. rufi- 

 ventris (Dumeril & Bibron). 



