Chap. IH. GENERA OF EMYDOIDiE. 433 



localities in Mississippi ; of Mr. G. Stollcy, from Arkansas and Texas. Professor 

 Baird has sent specimens to me, collected by Dr. Hoy in south-western Missouri, and 

 others from Tarboro', North Carolina. It is considered everywhere at the South 

 as tlie most delicious kind of Terrapene. The young are represented PI. 1. 

 fig: 13, and PI. 2, fig. 4-G;i the eggs (PI. 7a, fig. 20-23) vary much more 

 in size and form than those of any other species in the family. This is also 

 the case with the adults, which, as far as the form is concerned, vary much 

 more than Ptychemys rugosa, though the range of variations in the colors is less. 

 Some are very elongated, and narrower in front and behind than across the 

 middle ; " others are broad, and evenly rounded at both ends.'' Some are flat ; others 

 very high, especially behind the shoulders;* and some have a very blunt head, while 

 in others the snout is more prominent. Before I knew that the blunt form of 

 the head was an embryonic feature which is sometimes preserved to advanced 

 age, I had distinguished such specimens under the name of Ptychemys Hoyi. 

 The most prominent character of the species consists in the comparative smooth- 

 ness of the upper jaw, and the slight emargination of its edge, which is rather 

 arched than notched ; the lower jaw, however, is distinctly serrated, though less 

 evenly than in Ptychemys rugosa and mobiliensis, and provided with a smaller 

 and less prominent hook. 



Ptychemys mobiliensis, Ag!" It is easily distinguished from the other species 

 of the genus by the great height of the anterior part of the back, and still 

 more by the serrature of both jaws; the lower, however, is more strongly and 

 more coarsely serrated than the upper, which is deeply notched in the centre, 

 with a prominent tooth on each side ; there is a marked hook in the lower jaw. Its 

 geographical range is believed to be rather limited. It is said not to be found 

 west of Mobile Bay, where it is common, and to abound in Pensacola. I 

 owe all the specimens I have from these localities to Drs. Nott and Holbrook ; 

 but others were sent to me from New Orleans by Professor Chilton, and from 

 ^k* f'-i Guadalupe Mountains,- Pecos River, Texas, and New Leon, near Cadereita, Mexico, 

 by the Smithsonian Institution, so that this species extends much further west than 

 is generally supposed. Tliere can be no doubt upon the point, as, besides the 

 specimens sent to me by the Smithsonian Institution, I have received young speci- 

 mens, collected in Texas, by Mr. G. StoUey. The young are represented PI. 3, fig. 

 14-lG; the eggs (PI. 7a, fig. 24 and 2o) are larger and less variable than those 

 of Ptychemys concinna. 



* This is Gray's Emys anniilifcm. * This is the Testmlo (Emys) floridana, LeC. 



' This is the Testudo (Emys) concinna, LeC. * First described l)y Dr. Ilolbrook as Emys mo- 



* Tills is tlie Emys oriiata of Bell. biliensis, vol. 1, p. 71, pi. 9. 



55 



