248 Illinois State Laboratory of Natural History. 



cealed at the sides by fleshy lips. Legs strong, with marginal 

 and interdigital webs, anterior tvith a few transverse scales 

 above, posterior with a single large scale. Digits 5-5, the first 

 three of all the feet with claws, the two outer without claws 

 and concealed in the webs. 



Dorsal surfaces of head, legs, and carapace olive-brown, 

 the carapace with small obscure blackish spots and short lines, 

 and with a pale margin preceded by a blackish line. Plastron 

 and the head and legs beneath white and unmarked. A pale, 

 black-edged stripe extends from the snout to the eye, and is 

 continued behind tha latter backward and downward to the 

 side of the neck. 



Length of carapace, ().5(); width, ").(>(); depth, with the 

 plastron, 1. 



In running water throughout the State. Mackinaw Creek, 

 Woodford Co.; Quincy; Illinois River, Peoria; Wabash R., Mt. 

 Carmel (Ridgway); Ohio River, Cairo. 



The leather-back is never found at any great distance 

 from water. The time for oviposition is in the fore part of 

 July, and at this season the female searches out a sloping 

 bank up which she creeps a short distance and deposits her 

 eggs in a hole dug in the sand. At other seasons these turtles 

 remain in the water, though they may often be seen at its 

 edge basking in the sun. They are expert swimmers and 

 can move with considerable speed against a strong current. 

 Hundreds of them may be seen at the foot of dams across the 

 Illinois River in July, where they apparently collect in at- 

 tempting to get further up the stream. They take the hook 

 occasionally, and their flesh is highly esteemed as food. 



ORDER SAURIA. 



Body elongated and covered with numerous small imbri- 

 cated scales. Four limbs (rarely wanting). Shoulder girdle 

 always present. Eyelids and external organs of hearing pres- 

 ent. Jaws with teeth set in a continuous groove; jaws not 

 dilatable. Heart with three chambers. Urinary bladder pres- 

 ent. Oviparous, with a few excejitions. 



Our li/ards are almost confined to the southern third of 

 the State, where two species are very common. The joint 



