440 REPORT OF NATIONAL MUSEUM, 1893. 



spots opi)Osite tbeir lateral angles as well as their intervals. Head 

 without marking, except a faint trace of a pale line from the eye to the 

 border of the mouth below it. Inferior surfaces yellow. Tail white, 

 with five black cross bands, of which all but the first are complete rings. 



Gastrosteges (ventrals), 186; urosteges (subcaudals), 20; scale rows, 

 27; total length, 1.245mm. 



Variation. — The characters upon which this form were originally 

 based, viz, the small size of the scales on canthus rostralis and the 

 absence of either light or dark borders to the dorsal rhombs do not 

 seem to hold in a larger series, for of the additional specimens which I 

 have seen some have the cauthal scales of normal size, while in nearly 

 all the specimens there are traces at least of the borders to the dorsal 

 spots, these borders becoming apparently less distinct as the snakes 

 grow larger. The only character which seems to fairly distinguish this 

 form as a subspecies is the bright cinnamon red color of its upper sur- 

 face, at least in the large specimens. 



Geograpliical distribution. — This subspecies was originally described 

 from a specimen the habitat of which was not known. Since then I 

 have seen, thanks to Dr. C. Hart Merriam, several large specimens from 

 Twin Oaks, San Diego County, on the Pacific slope of the coast ranges, 

 which fixes the range of the form. A young specimen in the National 

 Museum (No. 88.-)6), somewhat darker and less bright red than the 

 others, probably either on account of its age or the long time it has 

 been in alcohol, is recorded as collected by A. W. Chase at San Fran- 

 cisco, November, 1875, but it is probably very doubtful if the specimen 

 really came from the immediate vicinity of that city. 



Hahits. — Nothing special is known of the life history of this form, 



TuK Pkairie Rattlesnake, 



Cy-ofahis coiijiin-iifus,^ Say. 



Plate 12. 



ISlS.—Wrofalhiiisviridis, Rafinesque, Am. Month. Mag., iv, 1818, p. 41. 



1823.— CrotnJus coxfliientus, Say, iu Long's Exped. Rocky Mts., ii, p. 48. — Baird 

 and GiRARD, N.Am. Seip.,p. 8 (1853). — Baird and Girard, iu Marcy's 

 Expl. Red River, p. 214, Zool., pi. i (1853).— Hallowell, Proc. Phila. 

 Acad., 1856, p. 250.— IUird, Pac. R. R. Rep., x, Whipple's Route, p. 40 

 (1859).— Baird, Mex. Bound. Surv., ii, Rept., p. 14 (1859).— Cooper, Pac. 

 R. R., Rep., XII, pt. Ill, p. 295 (I860).— Cooper, Amer. Natural, 1869, p. 

 124.— Cope, Proc. Phil. Acad., 1859, p. 337 (I860).— Cope, Bull. U. S. Nat. 

 Mus., No. 1, p. 33 (1875).— Cope, Amer. Natural., xiii, 1879. p. 435.— Cope, 

 Bull. U. S. Nat. Mus.. No. 17, p. 24 (1880).— Yarrow, in Wheeler's Surv. W. 

 100 Mer., v,p. 530 (part) (1875). — CouKS and Yarrow, Bull. Geol. Surv. 

 Terr. (Haydeu's), iv. No. 1, Feb., 1878, p. 262.— Cragin, Trans. Kansas 

 Acad. Sc, VII, p. 121 (1881).— Garmax, Rept. Batr. N. Am. Ophid., pp. 114. 

 172 (1883).— Garman, List N, Am. Rept. Batr., p. 34 (1884).— Stejneger, 



* From the Latin cow^mphs, flowing together; with reference to the spots on the 

 Leek of the type specimen running together into a longitudinal mark. 



