158 



deeply serrated. The bridge is narrow from front to back, the width 

 being contained in the length of the plastron about three times i-^r more. 

 It rises little toward the carapace, and this contributes to the apparent 

 flatness of the shell. Hinder border of the plastron with a deep notch. 

 Longest suture that betAveQu the abdominals ; the shortest, that between 

 the humerals. Digits all strongly webbed. Hind feet very large and flat. 



The ground color of the carapace varies from olive to dark brown. 

 This is variegated with numerous lines aud stripes of yellow. On the 

 vertebrals the lines tend to run longitudinally. On the costals broad 

 yellow bands divide each scute into three or four areas, inside of each of 

 which are narrow concentric lines of the same color. The marginals are 

 marked with yellow and brown. The plastron is yellow, with some 

 splotches of brown on the bridge. The head, neck, feet and tail are all 

 dark green, with numerous longitudinal bands of yellow. The length of 

 the shell of large specimens is 12 inches. 



Habitat from Georgia to Texas and north to the Wabash Valley. 



Two shells of this species are in the State collection, which were sent 

 from Mt. Carmel, Illinois, on the Wabash River. No doubt it will be 

 found along the whole lower course of the Wabash. In the " Report of 

 the State Geologist of Indiana" lor 1875, page 499, Dr. G. M. Levette 

 reports the occurrence of this species in the Kankakee River. Dr. 

 XiCvette had given considerable attention to the study of our tortoises, and 

 it is quite probable that he was correct in his determination of the species. 

 I have had the opportunity of studying a number of specimens of 'this 

 species in the National Museum. 



Nothing appears to be known concerning the special habits of this 

 terrapin. It is undoubtedly entirely aquatic, as are its immediate relatives. 



Chrysemys labyrinthica, (LeS.). 



Emys labyrinthica, LeSueur, MSS. in 113, 13 ; Malacodemmijs geo- 

 graphica, in part, Agassiz, 1857, 4-> h 436; Boulenger, 1889, 84^, 90; 

 Ptychemys labyrinthica, G. Baur, MSS. 



Tlie type of this species was taken <>y LeSueur in the Wabash River, 

 probably at New Harmony, and is now in the Museum d' Histoire 

 Naturelle, at Paris. Both Agassiz and Boulenger regarded it as belonging 

 to Malademys geographica, but it is evidently not this species. Dumeril, 

 in his description, states that the lower jaw is denticulated and furnished 

 with a hook which fits into a corresponding depression in the upper jaw. 

 He correctly compares the species with C. hieroglyphica, but says that it 

 differs from the latter in the less elongated oval of the carapace and the 

 elevation of the vertebral line, the shell of hieroglyphica being much 

 depressed. The species received its name, as said by Agassiz, from the 



