147 



Habits. — The habits of this turtle are much like those of 2. agassizii. 

 It lives iu similar localities, captures the same kinds of food, and deposits 

 its eggs in the sand, just as agassizii does. One was found by myself on the 

 14th of March buried in the sand where the water was so deep that she 

 could only with diiEculty reach the surface with her probo?ci?. The head, 

 colored just like the sand, was drawn entirely under as soon as she saw 

 that she was observed. It was with a good deal of exertion that she was 

 dislodged. She was kept until the 13th of May, during which time she 

 could not be induced to eat anything. On being put into a ditch she 

 immediately buried herself in the mud, and when hidden she gave her 

 body some sidewise movements so that the mud settled over her as 

 though nothing had disturbed it. Here she remained a day and two 

 nights. Prof. Blatchley (94, '91, 34), states that he has seen them moving 

 freely about in the water as late as December 11, and as early as March 

 19. When hibernating they burrow in the mud at the bottoms of pouds 

 and streams. 



This specimen will bite severely, as several observers have had oppor- 

 tunity to learn. DeKay mentions the fact that one bit a dog and took 

 out a mouthful of hair. These turtles can run rapidly on the land, and 

 when in the water they swim with great swiftness, as any one knows who 

 has tried to catch them. Profs. S. P. and S. H. Gage have demonstrated 

 that both this species and T. midicus enjoy a true aquatic respiration. 

 They say that these animals often remain voluntarily under the water for 

 from two to ten hours consecutively. While under the water there are 

 about 16 movements of the hyoid apparatus each minute, and by means 

 of these the mouth and pharynx are filled with water and again emptied. 

 The mucous membrane of the pharynx is closely beset with filamentous 

 processes which have the appearance of the villi of the intestines, and are 

 abundantly supplied with blood. Analysis of the water in which a turtle 

 was kept some hours proved that it was deprived of its oxygen and filled 

 with carbonic acid. 



The number of eggs laid by this species is probably about the same as 

 for T. agassizii. The eggs are spherical, have a thick, brittle calcareous 

 shell, and under this a very tough membrane. The eggs are a little 

 larger than those of T. agassizii, an inch in diameter. LeSueur (S6, xv, 

 263) says that at New Harmony the females lay their eggs in April and 

 May in the sand along the river bank. He has found in them 50 or 60 

 «ggs, about 20 of which were ready to be laid. The others were proba- 

 bly the eggs of the next season. The young appear in August. This 

 turtle is highly prized as an article of food. 



