356 Illinois State Laboratory of Natural History. 



The species occurs throughout the State and is not uncom- 

 mon in northern and southern Illinois. Cook Co. (Kennicott), 

 Geneva, Delavan, Peoria (Jirendel), Mt. Carniel (Ridgway), 

 Cave in Rock, Grand Tov^^er. 



Form miniatus. 



Skin scabrous. Tail with no, or with a very slight, fin- 

 like expansion above and below. Color brownish red above, 

 salmon-red below. Terrestrial. 



Form viridescens. 



Skin smooth. Tail with a fin-like membranous expansfon 

 above and below. Color olive-brown above, pale yellow below. 

 Aquatic. 



The colors vary a good deal in both forms. The number 

 of red spots of the longitudinal series varies from one to seven, 

 and the number may not be the same on the two sides of the 

 same animal. In nearly grown young they are, at least occa- 

 sionally, wanting. In addition to the red spots of the longitudi 

 nal series there are often a few others farther down on the sides. 

 The limits of the two colors of the dorsal and ventral surfaces 

 are clearly defined, and they may be separated along the sides 

 by an obscure dark line. A pale vertebral stripe is not uncom- 

 mon. The males may be known by the enlarged posterior legs. 

 These limbs are used for clasping the females during sexual 

 union, and on the ventral surface of each is a series of trans- 

 versely elongate corneous black tubercles, which are doubtless 

 of service in maintaining the embrace. The digits are fur- 

 nished with similar corneous tips. The posterior legs of the 

 female are smaller than those of the other sex and lack the 

 tubercles. The form mitiiatas occurs under stones, logs, etc., 

 and ai)[)ears to be strictly terrestrial. The form riridcsceits^ on 

 the other hand, is always found in the water, either in small 

 streams or (juiet pools. The movements, whether on land or 

 in water, are not rapid, and specimens may be ca|)tured (|uite 

 easily with the hands. The food consists of insects, small 

 mollusks, and crustaceans, the latter constituting an important 

 element of the food of the aquatic form. The species eaten 



