96 HERPETOLOGY OF MICHIGAN. 



Natrix fasciata crythrogaster, Xotesteiu, 1905, 111. 

 Tropidonottis erytlirogaster, Smith, 1879, 6. 



Nerodia agassizii, Baird and Girard, 1853, 41-42. Miles, 1861, 233. 

 Xerodia sipedon, Baird and Girard, 1853, 38-39. Miles, 1861, 233. 



Description: Medium sized snakes of robust form; size three and 

 a half to four feet. Head decidedly swollen at the base of tlTe jaws, 

 rather narrow and elongate, with high and straight sides. The 

 muzzle bluntly sub-conical, so that the nostrils are directed upward 

 to some extent. The nostrils quite small and capable of being 

 closed. 



Dorsal scales generally 23-21-19-17; occasionally 21-23-21-19-17; 

 more rarely 23-25-23-21-19-17, and 23-21-19- (17). Labials nearly 

 ahvays 8-10, very rarely 9 (or 7) superior and 9 or 11 inferior 

 scutes in the series. Oculars 1-3, with rare exceptions 1-2 or 1-4. 

 Temporals 1-3 with occasionally 2 in the second row-. Ventrals 

 137-149, subcaudals 56-75. Anal divided. 



The coloration of this species has been well described by Cope 

 (1900, 970-971) : "In young individuals and in those generally in 

 which the epidermis has been removed, the normal type of color- 

 ation is seen to consist of three series of nearly quadrate dark 

 brown spots, with still darker borders, one dorsal and one lateral 

 on each side. These are so disposed that the two corresponding 

 lateral spots are opposite the intervals between the dorsals, and 

 thus appear to be connected by a light line. The longitudinal diam- 

 eter of the dorsal spots, amounting to three or four scales, is 

 the greater; just the reverse of what is the case with the lateral. 

 Of these lateral spots there are generally about thirty-two on 

 each side from the head to the anus, the spaces between equal to 

 or less than the spots, not greater, as in T. fasciata. While the 

 pattern is generally quite distinguishable on the posterior half of 

 the body, anteriorly it becomes confused, the lateral blotches stand- 

 ing opposite to the dorsal and becoming confluent, so that the back 

 appears crossed by lozenge shaped blotches extending to the ab- 

 dominal scutellae, and this separated on the sides by triangular 

 intervals of a lighter color. 



''Occasionally the color appears to be a dull and rather light 

 brown, Avith the back crossed by narrow transverse lines, with dark 

 (nearly black, but still not distinct) margins." Frequently the 

 general color is so dark that the animal is more or less uniformly 

 dark brow^n or black above, and in some of the black individuals 

 the belly is red (so called variety erytlirogaster). 



HaUts and Hahitat: This well known snake is common along 



