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Show 1905.] ON THE ANATOMY OF THE LEATHERY TURTLE. 291 8. Notes on the Muscular and Visceral Anatomy o£ the Leathery Turtle (Dermochelys coriacea). By R. H. Burne, B.A., F.Z.S. [Received March 20,1905.] (Text-figures 55-73.) In May 1904 the Council of the Royal College of Surgeons obtained a specimen of the Leathery Turtle (Dermochelys coriacea L.) from Japan, with the object, mainly, of adding the skeleton to the Museum. On account of the rarity of the animal, it was thought advisable to make also a careful dissection of the soft parts, more particularly of those that must of necessity be destroyed in tlie preparation of the skeleton. The notes taken during this dissection, arranged for easy reference and collated with previous descriptions of the anatomy of the animal, form the contents of the present paper. The specimen was a young female of the following dimensions :- centim. Total length (following the curve of the carapace). . 135 Length (between the bases of the flippers) ........... 68 Girth (under fore limbs) ........................................... 135 Girth (midway between the limbs)........................... 140 Girth (at base of hind limbs) ................................... 91 Length of fore limb, from its point of emergence from the body (following the outer curve)........... 82 Greatest breadth of hand........................................... 20 Length of hind limb (tibial border) ....................... 33 Girth of head at hinder extremity of the gape....... 53 From point of snout to inner canthus of eye........... 8*5 From point of snout to nostril ............................... 2‘5 In colour the animal was black above, blotched with irregular white spots, each of which measured on an average 1 - 2 cm. in diameter. The ventral surface of the body, limbs, and tail was dirty white, marked with irregular longitudinal bands and blotches of black. The six longitudinal areas into which the carapace is divided by seven bony ridges are approximately of equal breadth- 1 1 cm. in the middle of the trunk,- gradually narrowing towards the tail. There are six rows of scutes half embedded in the thick plastral integument-a double row along the mid-line, with two single rows about 1 1 cm. apart on either side. The true plastron-bones (text-fig. 57, p. 298) lie close beneath the deep surface of the integument, and form a ring whose lateral parts lie about half way between the mid-line and the lateral margin of the plastron. They do not seem to bear any particular relation as regards position to the superficial rows of scutes. |