( 330 ) 



years, whilst jif only the motst iintmiiieiit striae .ire coimtei 

 tortoise would uot exceed ten years. 



The steruniu is slightly concave, trnncated in front anti 

 margin being slightly excised and attenuated. 



Length of carapace in a straigiit line 



„ „ over curve 

 Width of carapace in a straight line 



„ „ over curve 



Depth of carapace 

 Length of sternum 

 Width of sternum 

 Length of cau<lal ]ilate 



AVidth of caudal idate 



Circumference of vertical section of carapace 



the age of this 

 thickened, the Innd- 



2 •_).!, 



26 " 

 10.1 

 24 i 

 10 



loi 

 o" 



4.1 

 41.'. 



in. 



A description of the sindl would be superfluous. The skulls of these Duncan 

 Island tortoises agree minutely with that of the type of T. ephippium, showing 

 especially the same want of dei)tli in the concavity of the palatal region, by which 

 this species is distinguished from 7'. nhinydoitii. It may be useful to give the 

 measurements of the skulls and cervical columns of the specimens examined : — 



For reasons which presently will become sufficiently apj)areut, I have compared 

 the cervical vertebrae jiarticularly with those of T. ubingdonii, to the description of 

 which I refer the reader. They are rather less slender, of a heavier build bnt 

 altogether smaller. The crests and ridges are less developed. In otlier respects 

 they are shaped of the same type, hut the third, seventh, and eighth show 

 distinctly specific characters. 



In the atlas the lateral portion of the neural arch is conspicuously constricted, 

 and in its broadest ]iart it is as wide as the triheilral zygajiopliysis ; this latter 

 is hiuger than that part of the bone which forms the roof of the neural arch. 



The tliird cervical vertebra (PI. XXI. fig. a) is jirovided with a high and 

 sharp neural crest extending the whole length of the bouc ; the haenuil crest is 

 also well develoj)ecl, though much lower than the neural. 



The sixth cervical vertebra has its haemal crest scarcely more j)r(iniinrnt tlian 

 the preceding vertebrae ; and its jiosterior condyle is nearly completely hipartite. 



The geventh cervical vertebra (PI. XXI. fig. b) is, relatively to its length, 

 much deeper than the corresponding vertebra of T. abiixjdoiiii* and the summit 

 of its neural crest is swollen, witliout excision in the middle. 



The eighth cervical vertebra (PL XXII.) is more solidly built than in 

 T. ubingdonii,-^ the grooves and impressions being much less conspicuous ; especially 

 the deep lateral imjiression, which is so characteristic of T. abingdonii, is entirely 

 absent in 7'. ephipjiiinn. 



In order to show the measurements of the several vertebrae as compared 

 with T. abingdonii, I have jirepared tlic following table: — 



• See Oi^Mt. Lanrl Tort.. I'l. I.. H-. ►. t ^-f-, T'- I- H- G. 



