REPTILIA 549 



the margins of the carapace just anterior and just posterior to the 

 bridge. If a dry musk turtle be disturbed, a drop of yellow liquid 

 can often be seen to appear at each one of the openings of the 

 ducts from the four musk glands. This liquid gives off a disagree- 

 able odor. If it touches hands or clothing, it is very difficult to 

 remove. 



Family Chelydridae. — The common snapping turtles and the alli- 

 gator snappers are the living members of this family. Both turtles 

 have rows of raised prominences along each side of the carapace; 

 and a row of large bony ossicles along the middorsal region of the 

 tail. The head is large and formidable. The alligator snapper has 

 a pair of wormlike appendages in the mouth, which it is said are 

 used to entice fish within reach of its xiowerful jaws. Both turtles 

 are a plain brown color dorsally and dirty white to black ven- 

 trally. The alligator snapper may attain a weight of ojie hundred 

 and fifty pounds, while the common snapper will seldom exceed 

 forty pounds. Large specimens of either turtle can easily amputate 

 a finger or possibly a hand. Both kinds of snapping turtles possess 

 scent glands very similar to those found in the kinosternids. This 

 family is an excellent example of discontinuous distribution. It 

 was long thought that it was confined to the Western Hemisphere 

 but a genus is also found in New Guinea. 



Family Emydidae. — Many turtles, diverse in habits and appear- 

 ance, belong in this large family. All of the "hard-shelled" pond 

 and river turtles commonly called "sliders," the painted turtles, 

 the red-bellied turtles, the box turtles and many others fall into 

 this group. While there is great variation among members of the 

 family, they all exhibit certain tendencies as well as fundamental 

 structural similarities. Many species are brightly colored. The 

 painted turtles have bright red colors patterned with dark green 

 and black. Different species of the genus Pseudemys possess vari- 

 ous types of prett}^ colorations. The wood turtle has a somber 

 carapace, a bright plastron with pleasing black spots, and a rich 

 reddish-orange skin on the legs and neck. The males of many 

 species of this family have long straight claws on the toes of the 

 fore feet. Members of this family are found on all the continents 

 except Australia. Emys hlandingii, found in the Great Lakes region, 

 is very similar to Emys orbicularis of Europe. 



