A Study of the Remarkable Tortoise, Testudo loveridgii Blgr., and the Morphogeny of the Chelonian Carapace.

Abstract

Testudo loveridgii has an excessively depressed soft‐shelled carapace, and is able to inflate itself to a certain degree. It possesses a bony carapace and plastron, but they are extensively fenestrated, incomplete, and similar in essentials to the juvenile stages of other species. Marginal plates five, six, and seven spread inwards in a unique manner, entering into the composition of the plastron and separating the hyo‐and hypoplastrons from each other. Their upper portions are extraordinarily shallow. The ribs in T. loveridgii become (usually) entirely absorbed, apparently by the osteoclasts which are present beneath the periosteum. A simulacrum of the capitular portion, soft like ligament, and formed chiefly of periosteum, persists for some while. The neural arch is vestigial and sometimes completely wanting, the neural plates being applied to the depressed centra to form the roof of the neural canal. Absorption probably takes place to some extent as in the ribs, but the arch is never more than a simple extent as in the ribs, but the arch is never more than a simple layer of bone, without spinous processes. The jaws, together with their investing horny sheaths, are denticulated with remarkable regularity. Copyright © 1922, Wiley Blackwell. All rights reserved