AMPHIBIANS AND REPTILES. 215 
Genus CHELYDRA Schweigger. 
The Snapping Turtles. 
Chelydra serpentina (Linnzus). 
PLATE 58. 
Snapping Turtle. Snapper. Logger Head. Logger Head 
‘Tattle; 
Carapace broad, slightly oval, as viewed above, with greatest 
width about opposite fourth vertebral plate or last fourth of its 
Snapping Turtle. Chelydra serpentina (Linneus). (Young.) 
length. In form smaller, entire in front, and serrated behind. 
First 2 vertebral plates broadly octagonal and widest of series. 
Posterior margin of first vertebral plate slightly notched to re- 
ceive second, others following with posterior borders slightly 
concave. Second lateral plate largest. Marginal plates all small 
anteriorly and narrowly elongate, but becoming broad and with 
distinct angles along hind edge. Down middle of back each 
median vertebral plate has an elevated osseus crest which forms 
