1915.] NATURAL SCIENCES OF PHILADELPHIA. 119 



line extending the entire lengtli of the carapace, and the groups of 

 radiating yellow lines marking the costal plates. 



The carapace is chocolate-brown in color with characteristic 

 radiating yellow lines on the upper surface of the costal plates and 

 subparallel yellow bands extending outward on the external margins; 

 each plate is marked with regular concentric subrectangular grooves. 

 Plastron (closed) 5f inches in length and 3| inches in width; uniform 

 yellow in color with a reddish-broAvn spot on the external posterior 

 angle of each plate; all plates showing parallel grooves along the 

 median line, and in the case of the abdominal plates these grooves 

 make a right angle at the median anterior corner of the plate and 

 extend laterad reaching the margin. Under side of marginal plates 

 yellow with irregular markings of brown. 



. In the one specimen taken, the posterior end of the shell is some- 

 what mutilated. 



9. Platypeltis ferox Schweigger. Plate I, figs. 1, 2, 24; II, fig. 6. 



This species is common throughout the swamp. Adults, young 

 and eggs were collected, and the field notes show that this turtle 

 was recorded from Billy's Island, Honey Island, Floyd's Island, 

 Mixon's Hammock, Billy's Lake, Minne Lake and Sweet Water. 

 This species is doubtless to be found in all parts of the Okefinokee, 

 and is especially abundant in those places where the water is deep 

 and the bottom soft. The natives claim that soft-shelled turtles 

 are to be found wherever there are alligators, and this fact seems 

 to be borne out by the observations made on these turtles. On 

 May 31, 1912, an attempt w^as made to seine a " 'gator hole" on the 

 Honey Island Prairies. Before seining, Bryant Lee went over the 

 hole "grunting," a method locally used to start the aUigators, which 

 animals, it is claimed, will respond to this peculiar vocal accomplish- 

 ment and show their presence by rows of bubbles on the surface by 

 which they may be followed. In this instance the supposed alligator 

 was pursued for some distance, only to prove to be a large Platypeltis. 

 It is not improbable that the deep, secluded "'gator holes" may 

 furnish a favored retreat for this turtle whose ability to defend 

 itself by its powerful mandibles and snake-like bite is well known 

 and may be sufficient protection against the alligator itself. Accord- 

 ing to the Lees, this turtle is very active and can use its legs to a 

 remarkable degree, especially wdiile in the water, and plenty of 

 evidence was secured to show that its legs and knife-edged beak were 

 no mean weapons. A captured specimen, a foot or more in length, 

 which was kept around the camp for several days, showed a sur- 



