138 HERPETOLOGY OF MICHIGAN. 



narrowly oval in outline, and considerably arched. Young speci- 

 mens haye a prominent keel, but this becomes obscure with age. 

 Plastron yery narrow and short, not nearly filling the opening of 

 the carapace, rounded anteriorly, emarginate posteriorly, the 

 anterior part slightly movable on a transverse hinge between 

 the pectoral and abdominal scutes. All of the plastral scutes in 

 the adults separated b}^ areas of skin. Head large; snout tapering 

 and conical. Skin soft and everywhere provided with fleshy 

 papillae, those on the neck in rows, and two to four elongated ones 

 on the chin and two on the anterior part of the throat. Several 

 long curved scales on the anterior side of the foreleg near the foot, 

 and several on the heel. 



The color of the carapace in voung specimens is dull olive or 

 brown ; in old specimens it is blackish brown. The plastron varies 

 from dark yellow^ to brownish black. Skin dark greenish olive to 

 dark olive brown, marbled with light olive or yellowish olive. Two 

 yellowish lines extend backward from the snout, one passing below 

 and the other above the eye and ear. 



Hahits and Hal)ltat: The musk turtle is quite aquatic in habits, 

 being found most commonly- on the bottom in ponds and lakes. 

 The carapace is very often covered with a thick growth of algae, 

 so that it is difficult to detect when lying in a patch of aquatic 

 vegetation. 



Hay (1892a, 562) states that "They lay their eggs on shores in 

 holes that they have dug in the sand with their hind feet. The 

 eggs are from three to five in number, of an elongated elliptical 

 shape, a little more than an inch long, and have a hard, smooth 

 shell." Newman (1906, 147-148) records the following notes on the 

 breeding habits : "On onl}- one occasion did I have the good fortune 

 to observe Aromochelys in the process of nesting. When I first en- 

 countered the little "tortoise she was digging in some soft soil, using 

 all four feet and her snout. On my approach she abandoned her 

 work and wandered about for full}^ an hour trying different places. 

 Finally she selected for nesting a decayed stump that had rotted 

 down level with the ground. She dug with fore-feet and hind-feet 

 a shallow hole about two inches wide and of about the same depth, 

 and deposited two eggs therein. After covering these eggs with the 

 excavated debris, she w^ent her way. The form and Avorkmanship 

 of this little nest were of an inferior order as compared with those 

 of other species of tortoise I have observed. 



"Specin>ens were captured on land with eggs in the oviducts, 

 ready to be laid, on the following dates : June 11, 16, 20, 22, 23, 



