The =phalanges=. The first and fifth digits both have two phalanges, the second, third, and fourth have each three. The distal phalanx of the first digit is stout and curved, and bears a horny claw; those of the other digits are flattened and more or less pointed. [Illustration FIG. 40. A. ANTERIOR LIMB OF A YOUNG HAWKSBILL TURTLE (_Chelone imbricata_) × 1/4 (Brit. Mus.). B. POSTERIOR LIMB OF A LARGE GREEN TURTLE (_Chelone midas_) × 1/8 (Camb. Mus.). 1. humerus. 2. radius (almost hidden by the ulna). 3. ulna. 4. radiale. 5. intermedium. 6. ulnare. 7. centrale. 8. carpale I. 9. carpale IV. 10. pisiform. 11. first metacarpal. 12. femur. 13. tibia. 14. fibula. 15. tibiale intermedium and centrale fused. 16. fibulare. 17. tarsale 1. 18. tarsale 2. 19. tarsalia 4 and 5 fused. 20. first metatarsal. 21. fifth metatarsal. I, II, III, IV, V, digits.] THE PELVIC GIRDLE. The pelvic girdle consists of three bones; a dorsal bone, the =ilium=, an anterior ventral bone, the =pubis=, and a posterior ventral bone, the =ischium=. All three bones contribute largely to the formation of the =acetabulum=, with which the head of the femur articulates. The =ilium= is a small slightly curved bone, which unites ventrally with the pubis and ischium, and extends dorsalwards and backwards to meet the distal ends of the sacral ribs. The =pubis= is the largest bone of the three; its distal end forms a wide bilobed plate, the inner lobe meeting its fellow in a median symphysis, while the other lobe or lateral process extends outwards. Attached to the symphysis in front is a cartilaginous =epipubis=, while behind, the two pubes are terminated by a wide rounded cartilaginous area. The =ischium=, the smallest bone of the three, is flattened and like the pubis meets its fellow in a median symphysis. A narrow band of cartilage connects the symphysis pubis with the symphysis ischii, and separates the two =obturator foramina= from one another. THE POSTERIOR LIMB. This is divisible into three portions, the =thigh=, the =crus= or =shin=, and the =pes=. The =thigh= includes a single bone, the =femur=. The =femur= (fig. 40, B, 12) is a short thick bone, with a prominent rounded =head= articulating with the acetabulum. Behind this head is a deep pit, beyond which is a roughened area corresponding with the great trochanter of mammals. The distal end is expanded and somewhat convex. The bones of the =crus= or =shin= are the =tibia= and =fibula=. These are both straight rod-like bones with expanded terminations which closely approach one another, while elsewhere the bones diverge considerably. The terminations of all three of the leg bones are formed by epiphyses. The =Pes= consists of the =tarsus= or =ankle=, and the =foot=, which is made up of five digits.