ORDER OPHIDIA. 269 



Some of these trigonocephali with double plates 

 under the tail have the head furnished with plates.* 



Others with small scales on the head, have double 

 plates under the tail, excepting the little end, which 

 is furnished both below and above wdth small im- 

 bricated scales, and is terminated by a small sting.f 



Of this number is, 



Tlie Lozenged Trigonocephalus. ( Crotalus Mutus. 

 Lin. Coluh. Alecto, Sh.) Seb. II. Ixxvi. 1. La- 

 diesis Rhomheatay Pr. Max. 5. liv. 



Yellowish, the back marked with large brown, or 

 black lozenges. Its scales are raised in the middle. 

 It reaches six or seven feet, and is not less formidable 

 than the rattle-snakes. 



The Vipers (Vipera, Daud.), 



Confounded for the most part with the adders, by 

 Linnaeus, as having also the plates of the under part 

 of the tail double, ought to have been separated 



Boodroopam, Russ. Serp. Corom. ix., which has sometimes two or three 

 entire plates under the origin of the tail, but this is only an individual 

 accident. Add, Cophias Bilineatus, pr. Max. 5. liv. C. Atrox ; C. Jacaraca. 



* M. Fitzinger reserves the name of Tkigonocephali to this subdi- 

 vision. 



\ It is the genus Luchenis of Daudin, adopted by Fitzinger, but badly 

 characterized. Its subcaudal plates are certainly double as far as near the 

 end, where there are only small scales. The Prince of Wied represents it 

 perfectly. 



