BATRACHIANS AND REPTILES OF ONTARIO. 15 



These snakes can only strike a distance equal to about one-half the 

 length of the body. They need not necessarily be coiled to strike, for this 

 they can do on either side, as far as the position of the body will permit 

 them to reach. • , 



Rattlesnakes are ovoviviparous and not very prolific. -Prof. Cope 

 found nine eggs in the body of a female thirty-seven inches long. 



The Rattlesnakes may be distinguished from all other Canadian 

 snakes by the following well marked characters : Maxillary without solid 

 teeth, but provided with a long erectile, perforated poison fang on each 

 side in front ; a deep pit between eye and nostril. Body stout ; head large, 

 flat, triangular, on a slender neck; pupil elliptical, placed vertically. Tail 

 provided with a rattle composed of horny rings, which are modified scales. 



Genus SISTRURUS. 



(15) Sistrurus catenatus. 



(Prairie Rattlesnake.) 

 This species formerly occurred in the meadow lands at the western 

 end of Lake Erie, and has been found from there north to the Georgian 

 Bay. It is now nearly extinct. Though its bite is very dangerous and 

 may cause death, its venom is not so powerful as that of the next. 



Genus CROTALUS. 



(16) Crotalus horridus. 



(Common Rattlesnake.) 

 Formerly common and generally distributed throughout the Province, 

 but always most abundant in rocky places. Now nearly extinct. Very 

 venomous. 



Order LACERTILIA. (The Lizards.) 



This order is poorly represented in Ontario, only three species as yet 

 having been found in the Province, and these all belong to one genus. 



The characteristics of animals belonging to this order are : body 

 covered with scales ; limbs four, distinct, rarely rudimentary. Tail usually 

 long and in many cases very brittle, easily broken by a slight blow, or if 

 the animal is held by it. Tongue free ; jaws always with teeth ; mouth not 

 dilatable ; toes having claws. 



Family SCINCIDyE. (The Skinks.) 



Head regularly shielded, scales smooth, body fusiform or sub-cylin- 

 drical. All the species are quite harmless and feed upon insects. They 

 are fond of basking in the sun and rarely show themselves unless the 

 weather is bright and warm. 



So far as is known at present, all our species are ovoviviparous. 



