514 FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



with the vertebrae. The anteriormost of this is are fused. Eggs are 38 to 41 mm. in diameter, 



the nuchal. Lateral to the neurals are a paired white, with a mucilaginous coating, 



scries of plates which fuse with the ribs. These Loggerhead turtles. — The distinguishing feature 



are the costals. The outermost edge of the in these turtles is the presence of five or more 



carapace, enclosing the costals, consists of a pairs of costal shields instead of the four pairs in 



series of plates called the marginals. the hawksbill and green turtles. Two pairs of 



Green turtles. — These are characterized by a large shields, the prefrontals, are found on the 



single pair of large shields, the prefrontals, on top of the head between the eyes. Five or more 



top of the head and between the eyes. Four costal shields are present on each side, the first 



costal only are present on each side. The shields one of each row making contact with the nuchal, 



of the carapace do not overlap as they do in the Limbs are paddle-shaped, each with two claws, 



hawksbill except slightly when very young, and Sexual dimorphism of the tail is a feature of this 



the margin of the carapace is smooth. The limbs species, similar to the leatherback. Eggs are 



are paddle-shaped and possess only one claw approximately 42 mm. in diameter and are white 



except in occasional aberrant individuals which and soft. Deraniyagala (1943, 1945) has good 



have two. evidence that the loggerhead has broken up into 



The tail of the female barely reaches beyond several subspecies or races, 



the margin of the carapace. The tail of the male Kemp's loggerhead is distinguished by being 



reaches some distance beyond. The eggs are olive green in color dorsally, whereas the Atlantic 



soft-shelled and white in color and not quite loggerhead is brown or red. The former possesses 



spherical, between 40 and 46 mm. in diameter. four enlarged inframarginal shields along the outer 



The size does not usually exceed a carapace edge of the marginals. Each of these has a pore, 



length of 36 inches and a weight of 200 pounds. The neurals are equilateral in a continuous scries, 



although 850 pounds has been recorded. The Atlantic loggerhead, on the other hand. 



The green turtle is valued principally for use has only three enlarged inframarginals which do 



as food. not possess pores. The neurals in this species 



Hawksbill turtles. — Like the green turtles, these have elongated posterolateral sides and are some- 

 have only four pairs of costal shields. They times interrupted by costae. The Atlantic log- 

 differ in that they overlap, and the overlapping gerhead has two-clawed limbs. Those of Kemp's 

 edges are rough and serrated. The margins of turtle are three-clawed. Three and a half feet is 

 the carapace are markedly serrate, each marginal a good length for the carapace of the loggerhead, 

 shield projecting from the posterior end as a The weight rarely exceeds 350 pounds. Kemp's 

 pointed extremity. The marginal serration is loggerhead rarely exceeds 2 feet in length. It is 

 less noticeable on the anteiior end of the animal. ,^jj^ ^j commercial importance. It is nevertheless 

 Two pairs of large shields, the prefrontals, are ^^-^^^ although inferior to the green turtle, 

 located between the eyes on top of the head. i,a//*,,,6acH«,y/..,.-The carapace of this species 

 The paddle-shaped limbs are each equipped with • f, , r f ,, , i i i t^ 

 , f mi • fill IS soft and free from the vertebrae and ribs. It 

 two claws, rarely one. Itie jaws torm a hooked . , . ,  i • - 

 beak from whence the name "hawksbill" is derived. '^ ^"^•^'•^^1 ^'t^^ s"^o«th skin instead of horny 



Sexual dimorphism of the tail is the same as shields. Seven promment ridges extend down the 



in the green turtle. In males the two shields in back. In the male the tail extends beyond the 



the center of the top of the head, the frontal and hind limbs when extended. The eggs are soft and 



frontoparietal, are separate. In the female they white and from 50 to 56 mm. in diameter. 



KEY TO THE GULF OF MEXICO SEA TURTLES 



1. Back is covered with leathery .skin. Leatherback, Luth, or Trunk Turtle 



Dermochelys coriacea 

 Back covered vviith shield.s or plates 2 



2. Five pairs of .shield.s or plates along the back. Color uniformly brown, black, or olive green 3 



Four pairs of shields or plates along the back. Color brown or black mottled with yellow 4 



