GROT ALID^E. CXII. 199 



290. AGKISTROEJON Beauvais. (ay/ciarpoi/, hook ; oScoi/, tooth.) 

 a. Loral plate present. (Agkistrodon.) 



578. A. contortrix (L.). COPPERHEAD. COTTON-MOUTH. 

 Hazel brown; top of head coppery-red; back with a series of 15 

 to 25 V~ s h a P e( l blotches ; belly yellowish, with 35 to 45 dark spots 

 on each side; loral plate present. Scales 23. V. P. 150 to 155. 

 L. 40. N. E. to Wis. and S. in damp places, becoming rare N.; a 

 dangerous reptile. (Lat., one who twists.) 



aa. Loral plate wanting. (Toxicophis.) 



579. A. piscivorus (Holbrook). WATER MOCCASIN. BLACK 

 MOCCASIN. Greenish brown with 20 to 30 dark vertical bars, 

 often obscure; belly black and yellow, blotched. Scales 21 to 25. 

 V. P. 138 to 145. L. 50. Aquatic, N. C. to S. 111., Ark. and S., 

 often resting on overhanging bushes over streams watching for 

 frogs and fishes. The most dangerous of our snakes. (Lat., fish- 

 eating.) 



291. SISTRURUS Garman. (o-iorpoi>, rattle ; oty>d, tail.) 



580. S. catenatus (Rafinesque). PRAIRIE RATTLESNAKE. 

 MASSASAUGA. Brown or blackish with about 7 series of about 

 34 deep chestnut blotches, these blackish exteriorly and edged with 

 yellowish ; a yellowish streak from pit to neck ; body sometimes all 

 black. Scales 23 to 25. V. P. 135 to 150. L. 30. Prairies, Ohio 

 to Min. and S., abundant in grassy fields where not exterminated. 

 Another species (S. miliarius L.) occurs S. (Lat., forming a 

 chain.) 



292. CROTALUS Linnaeus. (tcporaXov, rattle.) 

 a. Scales in 23 to 25 rows. 



581. C. horridus L. COMMON RATTLESNAKE. Yellowish- 

 brown of various shades, with 3 rows of confluent irregular brown 

 spots, forming zigzag-shaped cross-blotches ; tail black ; a pale line 

 from mouth to eye with a dark patch below. V. P. 165 to 175. 

 L. 60. N. Eng. to Rocky Mts. and S. in rocky places; once com- 

 mon, but nearly exterminated in well-settled regions. 



aa. Scales in 27 to 29 rows. 



582. C. adamanteus Beauvais. DIAMOND RATTLESNAKE. 

 Brown, with 3 series of complete brown yellow-edged rhombs. 

 V. P. 165 to 180. Va. to Miss, and S. (Lat., diamond-like.) 



" I only know thee humble, bold, 

 Haughty, with miseries untold, 

 And the old curse that left thee cold, 

 And drove thee ever to the sun 

 On blistering rocks. . . . 



