NOTES ON SOME TURTLES OF THE GENUS 
PSEUDEMYS. 
BY C. S. BRIMLEY. 
The genus Pseudemys comprises a number of large fresh 
water turtles found in the streams and ponds of North Amer- 
ica. These have the carapace marked with a more or less 
variegated pattern of light and dark colors, and are distin- 
guished from allied genera by the broad masticating sur- 
faces of the jaws, which are in the upper jaw divided by a 
longitudinal ridge parallel to the margin. 
The species dealt with in this paper fall more or less natu- 
rally into three groups, which are characterized as follows: 
Group I. Upper jaw with a notch at the symphisis and a 
cusp or tooth on each side of the notch. Lower jaw, at least, 
strongly serrated. Ridges in masticating surfaces of jaw 
tuberculate. 
Group II. Upper jaw without either notch of cusps, other- 
wise as under Group I. Plastron always yellow, unblotched. 
Group III. Upper jaw notched at symphisis, but without 
cusps. Edges of jaws not serrated. Ridge in masticating 
surface of jaws not tuberculate. 
Group I comprises three nominal species, P. rubiventris 
LeConte, P. alabamensis Baur, and P. texana Baur. Of 
these the first and last are certainly distinct species, but the 
second, of which I have seen no specimens, may be the same 
as the first. 
Of P. rubiventris I have seen only one specimen, this be- 
76 [June 
