316 DE. HANS GADOW ON EEMAINS OF SOME GIGANTIC 



1st. The two marginals form a straight line, instead of being curved as in T. inepta, 

 T. triserrata, and T. sauzieri. 



2nd. The median notch is very slight dorsally ; absolutely wanting on the ventral 

 margin. 



ord. Ventrally the two marginals are strongly concave, forming a sharp and very 

 prominent ridge. 



Dr. Giinther, Monograph, p. 43, remarks that "a carapace with so straight a verte- 

 bral profile as that delineated and described of T. perraulti is not represented among 

 the specimens collected by Messrs. Bouton and Newton." Moreover, none of the 

 species described in his Monograph possess such a flat carapace. Our carapace 

 no. v., in its flatness and almost straight profile, agrees rather well with the figure 

 given by Perrault of his male Grande Tortue des Indes (' Memoires pour servir a 

 I'Histoire des Animaux et des Plantes,' Amsterdam, 1736, p. 395), but the anterior 

 marginals are very different. This may, however, be due to the inexactness of the 

 drawing, which also exhibits the curious anomaly of showing only four instead of the 

 usual five vertebral plates. 



Perrault remarks that the length of the shell was 3 feet, the tail 14 inches long, and 

 ending in a point " garni d'un bout semblable a une corne de boeuf." The length of 

 this horny spur is not mentioned ; judging from the figure, it would scarcely amount to 

 half an inch. 



Dumeril et Bibron, 'Erpetologie Generale,' vol. ii. p. 126, mention among other 

 points " la suscaudale simple, tres elargie ; la derniere de larangee vertebrale bombee." 

 If this implies that only the last vertebral plate possesses a hump, then this specimen 

 differs from both T. triserrata and T. inepta, because in the former all the vertebrals 

 are humped and in the latter the fourth and fifth ; on the other hand, T. indica s. 

 perrauUi agrees by the large caudal plate with T. triserrata, and dififers from T. inepta 

 and T. sauzieri. 



It is very probable that carapace no. V. belongs to a T. indica, and in this case there 

 can be no longer any doubt that Perrault's specimen came from Mauritius, a corrobo- 

 ration of Dr. Giinther's surmise. 



The Plastra. (Plate XLII.) 

 Plastron A. — Intermediate between T. triserrata and T. sauzieri. This plastron is 

 complete. Its greatest length is 39 cm., its greatest breadth 35-5 cm., indicating a 

 much broader Tortoise than T. sauzieri. It agrees in its ventral impressions with that 

 of T. sauzieri, but differs from the latter as follows : — 



1. The markings or shield-impressions in the inguinal region are more like those of 

 T. triserrata. 



2. The posterior margin of the plastron is decidedly and sharply curved upwards, 

 instead of showing a slight triangular swelling ; more like T. triserrata. 



