374 Illinois State Ldhoratory of Natural Ifisfonj. 



Very large, total length from six to eleven inches. With 

 twelve costal grooves. Body rather stout. Head large, wide, 

 convex above. Eye small but prominent. Mouth large. 

 Tongue large, obovate, wider than long, plicse radiating from 

 its posterior portion, no longitudinal groove. Palatine teeth 

 extending outside the inner nares. Mucous pores of head 

 mostly between the eye and nostril and in an elongate patch 

 above them. Cervical fold conspicuous. Limbs stron(>;; digits 

 depressed. Tail varying in length, shorter or longer than the 

 body, strongly compressed distally and regularly decreasing in 

 depth towards the tip. 



Color above brown or brownish black, with numerous irregu- 

 larly disposed round yellow spots. Brown or dusky below, 

 with scattered yellow spots or with most of the spots aggre- 

 gated on the sides and more or less coalescent. Throat with a 

 few spots or almost entirely yellow. Legs and tail spotted with 

 yellow. 



Length of an average specimen, from snout to the posterior 

 end of the anal slit, 4.19; from the latter point to tip of tail, 

 3.44. 



Throughout the State. Cook Co., Peoria ( Brendel), Nor- 

 mal, S. Illinois. 



The colors vary in individuals and with age. The yellow 

 spots may be distinct and bright yellow or so obscure as to be 

 scarcely discernible; they may be abundant and pretty regu- 

 larly distributed, or may be few in number and confined chiefly 

 to the sides of the belly. Young just from the water are nearly 

 uniform brownish black above, with no spots or a verj^ few 

 small ones, and are yellowish beneath, with perhaps a few indis- 

 tinct spots at the sides. At this stage some of the larval 

 characters are not yet lost. Rudiments of the branchiro are 

 apparent; the rami of the mandible are not so much arched, 

 nor so widely divergent as in adults; the palatine teeth are 

 strongly arched forwards; the tongue is smalljand elongate; 

 and the tail is shorter proportionally to the body than in adults. 

 Examples about five inches long ordinarily resemble the adults 

 in every respect except the proportional length of the tail, 

 which seems to increase with age. The following measure- 

 ments illustrate this change of proportions. The first are from 



