BATRACHIANS AND REPTILES OF OHIO. 103. 



Tail with a median crest of tubercles. — Chelydra serpentina — p. 139. 

 Tail without crest of tubercles. 40. 



Shell highest posteriorly. — Aromochelys odoratus — p. 139. 



Shell highest at the middle. 41. 



Plastron hinged, capable of closing, more or less completely, the- 



shell. 42. 

 Plastron without hinge. 43. 



Length of shell over 6 in. — Emynoidea blandingi — p. 141. 



Length of shell less than 6 in. — Terrdpene Carolina — p. 141. 



Shell with round yellow spots. — Clemmys guitaius — p. 140. 



Shell without round yellow spots. 44. 



Shell keeled dorsally, notched behind. — 



Graplemys geographicm — ^p. 140.. 

 Shell not keeled nor notched behind. 45. 



Plastron blotched with black. 46. 



Plastron not blotched with black. — Pseudemys hieroglyphica — p. 140. 



Middle plates of carapace opposite each other. — 



Chrysemys pida — p. 140.- 

 Middle plates of carapace alternating with each other. — 



Chrysemys marginata—'p. 140.. 

 Dorsal part or tail bright blue. 48. 

 Dorsal part of tail not bright blue. 49. 



Black, with 5 yellow lines. — Eumeces quinquelineatus — p. 125. 



Black, with 4 yellow lines. — Eumeces anthracinus — p. 125. 



A series of wavy lines runninsf across body. — 



Sceloporus undulatus undulatus — p. 123.. 

 No wavy lines running across body. 50. 

 Three yellow lines on each side of the body. — 



Cnemidophorus sexlineatus — p. 124. 

 A black and a white but no yellow bands on the sides. — 



Liolepisma laterale—p. 124. 

 With rattles at the end of tail. 52. 

 Without rattles at end of tail. 53. 

 Blotches on back numerous, smaller arranged in 7 series. Rattles small.. 



Length never over 3 feet. — Sistrunus cat'enatus catenatus — p. 137. 

 Blotches on back arranged in 3 rows, forming zig-zag cross-blotches_ 



Rattles large. Length 3}4-5 feet.— Crotalus horridm—p. 138. 

 With a pit between eye and nostril.— Ancislrodon contortrix — p. 137. 

 Without a pit between eye and nostril. 54. 

 Body uniformly qplored above, without markings. 55. 

 Body with markings above. 62. 

 Color brown. 56, 

 Color greenish or black. 57. 



Scales smooth.— Carphophiopsamoenus—p. T25. 



Scales rough. — Natrix fasdata eiythrogaster—'p. 131.. 



End of snout upturned. Body short and thick. — 



Heterodon platyrhinus — p. 126. 

 End of snout not upturned. 58. 



Scales rough. 59. , • ^ ,j. ,• 



Scales smooth.— Ltopelhs vernahs—v- 127.^ 



Greenish below. 60. ^ , . ,. 



Yellowish below. — Clonophis aesnvus — p. 128.. 



