CHELONIA." 



'PsLmilj—TESTUDINII)^. 



Genus Testudo, Auctorum. 



As far as I have been able to observe the structure of the osseous parts 

 of the Chelonian species properly referable to the Genus Testudo, and the form of 

 the bones and constituent parts of the shells of such small species as T. elongata, 

 there do not appear to be any characters entithng them to be separated generically, 

 and this remark is applicable to the tortoise described by Gray under the name of 

 ManomHa, and to the shell and bones of the animal referred by him to the genus 

 Scapia. There are various modifications in the form of the anterior elements of the 

 constituents of the plastron, and especially of the so-called clavicles or epiplastral 

 pieces, but these cannot be regarded as having any generic significance. 



A study of the figures of the skulls of the animals described by Giinther in his 

 admirable Monograph of the gigantic land tortoises, reveals, also, no generic difi'er- 

 ences, but a general uniformity in the skull and in the relations of its parts, viz., a 

 palatal region conforming more or less to one type, characterized by length, openness 

 and concavity ; the presence of a median ridge, the posterior portion of the palatal 

 surface, being, as a rule, defined by ridges from the pterygoid ; the premaxillaries 

 generally concave on the under surface ; the alveolar surface of the maxillaries with 

 a longitudinal, sometimes dentated ridge interior to its outer border, the inner margin 

 of the alveolar surface somewhat thickened and also ridge-like ; and the point of 

 union of the premaxillaries and maxillge, and the line of union of the former bones 

 with each other marked, more or less, by an eminence sometimes pointed, sometimes- 

 rounded. Now, in all these characters the skulls of the small radiated tortoises 

 resemble the Genus Testudo; Dr. Gray, however, considering that the mesial 

 alveolar ridge on their maxillaries was indistinct, separated them under the generic 

 term Feltastes. But the lower jaw, also, of these so-called Peltastes, conforms 

 to the Testudo type of structm'e. Dr. Gray has further separated tbe African 

 species of the radiated forms on the strength of the maxilla and premaxilla not 

 presenting any tooth-like eminences. The absence or presence, however, of such 

 structures in the skulls of the gigantic tortoises would never be considered as of 

 generic significance; and there is nothing to sanction its being regarded as such in 



' AU the Sepiilia described in this section were either observed or obtained on one or other of the Expeditions to 

 Yunnan, with, the exception of a few species of Chelonia indicated by. a + . 



£4 



