OPHIDIA CROTAL1DAE CAUD1SONA CERASTES. 609 







teen, the first and second margining a plate, which meets its fellow in front 

 of the geneials, and is in other species a continuation of the first, Gastro- 

 steges, 178; nrosteges, 84; joints of rattle, 9. The general tint of this 

 species is a bright salmon-red ; the scales of the inferior rows punctulate 

 with brown. 



Nasal plates distinct ; muzzle with small plates or numerous scales 

 above [as in cerastes and mitclielli}. Upper margin of canthus rostralis 

 with small scales like the others. Prenasal separated from rostral by scales; 

 superciliary not prolonged. Rostral broad as long ; head very obtuse, 

 rounded. Scales 25 rows ; 7 between superciliaries, 3 below orbit ; labials, 

 14 ; 2 very small preorbitals and 4 loreals. Pale-vermillion varied with 

 yellow on the sides of the belly, with numerous large reddish-bay hexagons, 

 which become transverse bands on posterior two-thirds of length ; yellow 

 below. Rattle subacuminate. 



This species is one of the most handsomely colored of the genus. Its 







affinities are with the C. mitchi'Ui, Cope; but it exhibits an even higher degree 

 of subdivision of the head shields. (Cope, descr. orig.) 



A single specimen of this richly colored species was procured at Canon 

 Prieto, a locality near Fort Whipple. It is not in the best order, as it was 

 procured under the untoward circumstances of a hasty retreat from hostile 

 Indians. The species is probably rare, as I never met with a second exam- 

 ple, while that one procured was regarded as a curiosity by the numerous 

 persons who came to see a "red rattlesnake". 



40. Caudisona (/Echmophrys) cerastes, (Hallow.). 



Crotalu* cerastes, HALLOW., Proc. Acacl. Nat, Sei. Phila., 1854, 95. Id., P. B. B. Re|>., 

 x, 1859, Williamson's Boute, Reptiles, 17. UEEBM., ibid., 24. BD., U. S. 

 & Mex. Bound. Snrv., ii, pt'. ii, 1859, Reptiles, 14, pi. 3. COPE, Check-List, 

 1875, 33. 



Caudisona cerastes, COPE, Proc. Acad. Nat, Sci. Phila., I860, p. . 



JEclnnophrys cerastes, COUES. 



Head small, with rounded angles; nose depressed, obtuse; rostral 

 as broad as high ; nostril in middle of a single large plate ; lateral edge of 

 superciliary plate elongated into a horn-like process over the eye. Two 



rows of scales between the suborbital series and the labials ; superior labials 

 39 z 



