AMPHIBIANS AND REPTILES. 221 
of each anal. Plates on plastron all with more or less angulated 
striez. Head large, heavy, depressed both above and below, and 
with swollen appearance posteriorly. A marked depression on 
middle of head above, and each side swollen convexly. Snout 
obtusely protruding, nearly equally as long as broad, and in 
profile sloping down inferiorly or towards throat. Eye moderate, 
socket about 4% in head to occiput, or a little longer than snout, 
lateral, and a little longer than deep. Mouth oblique, inferior, 
edge of upper jaw shutting over lower all around, so that man- 
dible is inferior and with convex surface. Upper jaw hooked in 
front. Edges of jaws sharp and horny, and when closed gape 
Mud Turtle. Kinosternon pensylvanicum (Gmelin). (Young.) 
appearing with a notch in front behind hook of upper jaw, and 
then convex, with bulge down. Mouth as viewed below 34 as 
long as wide. When viewed above profile of head would form 
a more equilateral triangle. Head and neck distensible for space 
equal to 34 length of carapace, and wrinkled skin on neck form- 
ing a fold on retracted head. Legs, feet and tail covered with 
soft skin and some few weak scales or scale-like tubercles. Scales 
perhaps best developed and strongest on soles and palms. A 
few large scales at bases of fingers and toes above. No scales on 
tail above. Limbs short, strong, and hind pair a trifle smaller. 
Claws 5 on each front pair, and 4 on each hind pair. ‘Those on 
