TURTLE. 363 



The first, AMYDA Mutica, (Fitz.,) was obtained by Baird 

 from the Alleghany River. 



ASPIDONECTES Spinifer, is the other soft-shelled turtle, 

 which is said to be " common in the western part of New 

 York and Pennsylvania." 



These turtles are not abundant high up the mountain 

 streams, but in the Ohio Tributaries of Western Pennsyl- 

 vania, where there are large dams and pools, they abound, 

 and are sometimes of larger size than represented by 



Family CHELYDROID^E. 



CHELYDRA Serpentina, (Schw.) The Suapping-turtle fol- 

 lows the streams of the mountain to a great height. In 

 saw-mill dams, even on small runs, he grows to his largest 

 dimensions. These large individuals are very old, as, ac- 

 cording to Agassiz, "specimens, 12 inches long by 9J wide, 

 are thirty-eight years old, and a specimen, marked forty- 

 five years old r only increased an inch in that time." High 

 up in the range they are frequently much larger than this, 

 and, consequently, must be patriarchs of the race whose 

 longevity no doubt has been insured by the salubrity of their 

 alpine home. They are hideous in their form, savage in 

 their habits, like other carnivorous animals, and from the 

 ferocity of their style of defence, mode of attacking their 

 prey, their ugly heads, with powerful jaws like the edges 

 of a sharp-cutting vice, protruding from the shield of a 

 rough, rocky shell, and accompanied by a long spinous 

 tail like that of the alligator, they present an appearance to 

 the last degree revolting.* They feed upon fish and water- 

 rats, young ducks and geese, attacking even full-grown ducks 



" Tliis originally Western species passed from St. Peter's Kiver through 

 Red River to Lake Winnipeg, giving a passage for the Trionyx feror 

 to Lake of the Woods ; also, the Upper Illinois communicates with 

 the waters of Lake Michigan, and thus reaches the chain of lakes 

 that open into the St. Lawrence River." 



* The fights of these reptiles are fierce and deadly, often pro- 

 tracted for hours. 



