AMASTRIDIUM, A NEGLECTED GENUS OF SNAKES.^ 



By E. R. Dunn 

 Of the Department of Zoology, Smith College, Northampton, Massachusetts. 



I have recently had the pleasure of examining several specimens 

 of a small snake from Central America, which is undoubtedly the 

 species described by Cope as Amastridium velife-imm.^ In 1886 Cope 

 mentioned the fact that this species possessed hypapophyses on the 

 posterior vertebrae ; ^ in 1892 he stated that the hemipenis had a 

 divided sulcus;* in 1894 he further described this organ as un- 

 divided, with divided sulcus, with well developed spines, and " caly- 

 culate not capitate," ^ and in 1900 he figured the hemipenis.^ Bou- 

 lenger ^ quoted the original description at the end of his account of 

 the Colubridae, omitting the genus from his key to the family as of 

 " doubtful position." In 1898 Boettger ^ redescribed it as FUisch- 

 mannia obscura. Giinther does not mention this snake in the Biolo- 

 gia Centrali-Americana. Two specimens collected by Robert I. Mat- 

 thews at Greytown, Nicaragua, are in the United States National 

 Museum, and a specimen from Cariblanco, Costa Rica, is in the 

 Museum of Comparative Zoology. 



I have also seen a single specimen in the U. S. National Museum 

 from Chicharros, Chiapas, Mexico, which agrees in detail with the 

 species described by Werner ® as MimoTneto'pon sapperi. 



These two species are unquestionably congeneric and should stand 

 as Amastridium, veliferum Cope and Amastridium sapperi (Werner) . 



They differ as follows : 



Velifennn: Loreal absent, ventrals 121-135, maxillary teeth 12-2, 

 no groove visible under magnification of 80 diameters. 



' Contributions from the Department of Zoology, Smith College, No. 110. 



^Proc. Acad. Nat. Sci. Philadelphia, 18G0, p. 370, " Cocuyas de Veraguas," Panama. 



»Proc. Amer. Philos. Soc, vol. 23, 1886, p. 495. 



*Amer. Nat., vol. 26, 1892, p. 481. 



» Idem, vol. 28, 1894, p. 840. 



• Report U. S. Nat. Mus., 1898, pi. 24, fig. 13. 



^ Cat. Snakes Brit. Mus., ser. 2, vol. 2, 1894, p. 352. 



8 Kat. Mus. Senekenberg., Rept., vol. 2, p. 69, San Jos4, Costa Rica. 



» Abh. Bayer. Akad. Wiss., 1903, vol. 22, pt. 2, p. 349, Guatemala. 



No. 2524 — Proceedings U. S. National Museum, Vol. 65, Art. II. 



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