vol 



18U1 



,j\''] procp:ei)Ings of tiik national mtskum. f;89 



Postociiliir l»aii(l reiicliiiii; niDntli anterior to cautliU8 ; ilor.sal rlioiiili.s »iii ii jmIit 



j,a()Uiul; uo jiucU .stripeH; scales -i.')-!) '<idamaiil, ii». 



aaa. Tail with browu or iudistinct bands, 

 /i. Rostral plate more elevated. 



Muzzle with the marginal scales larj,'er tlian tiit^ median; scales 'S.i-7 ; three 

 rows of brown dorsal spots, the median lar^o ; postocular band pass- 

 injj above cantbus oris C. cunfliuntuH. 



Eight smooth longitudinal plates on top of muz/.le; two loreals; scales twenty- 

 seven rows; a postorbital spot; live rows of dorsal spots; 



('. iiolyntirtua. 



Six smooth square plates on top of muzzle ; one loreal ; scales twenty-three rows; 



three rows of iloi sa! spots, the median large C. triiieriatua. 



fJ/J. Rostral plate less elevated. 



Eight smooth plates ou top of muzzle; scales in twenty-three rows; green with 

 black rings ; no postocular band C. leinduH. 



Small smooth scales on top of nnizzle ; one loreal ; colors pale ; subquadrate dor.-al 

 spots which beconni transverse bands posteriorly i'. iMjrix. 



Small keeled scales on top of muzzle ; two loreals ; colors contrasted; daik brown 

 spots above becoming first transverse rhombic and then cross-bamlH 

 posteriorly; a postorbital band passing above cauthus C. emjo. 



AA.. Nasal plate in contact with rostral; border of superciliary produced into a 

 horn -like process. 



Small smooth scales on top of muzzle; colors pale, the dorsal spots small; cross- 

 bauds on tail of the same color; scales twenty-one rows ...('. nrasl h. 



AAA. Nasal plate separated from rostral by scales: sujierciliary not jirolongcd. 



Rostral low; tail black-ringed; one loreal plate; yellow with (|uadrate punctii- 

 late brown dorsal spots, becoming cross-bauds posteriorly; 



C. milcliellii. 



Rostral low; tail brown and black-ringed; four loreal plates; red with d;irk 

 red spots becoming cross-bands C. pyirhui. 



Crotalus molosBua lid. aud Gird. 



Crolalun molon8U8 IU\. and iihd , Cat. Rept. N. Amer. 1>^.')3, p. 10; Haird, IT. S. et .Mex. 



Bound. Surv. Reptile, 18.VJ, p. 14 ; Cope Check List N. Am. Matraeh. and 



Rept. 1875, p. :V3; Cope and Yarrow U. S. G. G. Surv. \V. of iClOth .Mer. 



V, 1875, p. 533; Cope Proc. Acad. Phila., 1883, p. IJ. 

 Crotalus oniatun Ifallowell, Proc. A. N. 8. Pliila. vii, 1854, i;)-2, IJ. S. Pac K. \l. K\\,\. 



Rept., 1851); Parke's Rept. K'eptile.s. p. 2:<. 

 Icones. IJ. S. Pac. R. R. Rept. Reptiles, x.xiv, f. 5. Ihid., Park.-s liejit. tab. ii. V. 



S. and Mex. Hoiiinl. Siirv., tab. in. 

 Tlie Souoran region; as yet only near tlic .M.-.vifaii Itoiinilaiy. 



Crotalus adamauteua Heanv. 



Palisot <le Heanvois Trans. Amer. Philos. 8oc. iv. 17W. 3i'.-^ : Copo, Cbeck List N. Amer. 

 Hatr. Rept. 1875, p. 3.3. 



The subspecie.s «litrei' as lollow.s: 

 Entire tup of iiead covered with irregular flat scuta larger than the nsual Hoaie^; 

 body colors palerthan tail bauds; dorsal rhombs with trnnciited angles; 



oneloreal plate C. a. xr„tiih,iu.. 



Top of head with large i)lates on cantbus rostralis, but scales olsewhcru: two loreal 

 plates; dorsal rhombs complete, not paler than eaudal l»anil.s; hist 



caudal band a wide ring '• "• nditmanUut. 



Tror. N. M. 1>1 44 



