NOVITATES ZOOLOGICAE XXII. 1915. 431 



Material. — Including both specimens with double and undivided snpracaudal 

 scutes, the Tring Museum has 3 J c? and 7 ? ? entire ; the Royal College of 

 Surgeons' the carapaces of 2 c? c? (1 adult, the T3'pe, 1021, and 1, No. 1020, half 

 grown) ; and the British Museum 1 carapace of an adult S, and an adult ? stuffed 

 which is wrongly catalogued by Boulenger as the type of hololissa GiUith. 



Diagnosis. — Nuchal plate normally present ; gulars paired ; third cervical 

 vertebra biconvex ; front of carapace declivous, much lower than middle ; height 

 at nuchal plate more than 31% of straight length (32-40%) ; difference between 

 percentages of heights at third vertebral and nuchal plate 20% ; carapace strongly 

 dome-shaped and oval, very wide anteriorly, width at junction of second and third 

 marginals more than 40% (44-58%) ; front and hind marginals not everted and 

 not produced ; length over curve not more than 140%-(129-140%), generally less 

 than width over curve ; vertical height to marginals medium, very constant, 5-7% ; 

 size large, adult c? S 30-40-5 inches ; plastron medium, greatest percentage 88% ; 

 plates entirely smootli. Scutes of head and forelegs smooth, flat and level with 

 surface of skiu. 



General Remarks. — The Type of Dr. Giinther's description is undoubtedly the 

 adult S No. 1021 in the Hunterian Museum and not, as Mr. Bonlenger records, 

 the adult ? now in the British Museum, which latter, when the descrijition of 

 hololissa was published in 1877, was still living in the Zoological Gardens, London. 

 The history of this specimen was, that it was being taken as a present to the 

 Governor of Mauritius (Isle of France) on board the French corvette Gobe-Mouches, 

 in December 1808, when this vessel was captured by H.M.S. Nereida, Captain 

 Corbett, on December 18, and taken to the Cape of Good Hope. It was sent to 

 England by Admiral Bertie, who at that time commanded at the Cape, and it 

 lived at Petworth, the country seat of the Earl of Egremont, from August 1809 

 to April 1810. Its weight was 207 lb. Through the investigations of Monsieur 

 Sauzier we now know that this specimen was really an indigenous Se3'chelles 

 Tortoise ; but of course we do not know from which one of the numerous islands 

 it had come. The very large male (40-5 inches. No. 139) in the Tring Museum 

 is an exceedingly old animal — at least 300 years ; it weighed when alive 593 lb. 

 I obtained it through the late Mr. Carl Hagenbeck. 



No. 176 is remarkable for having no nuchal plate. 



Nos. 140 and 143 are evidently hybrids with T. daudinii, for while showing 

 all the general characters of T. gigantea they are very long and narrow and much 

 depressed, the "middle height" being less than half the "straight length," as in 

 daudinii. Although neither have the marginals everted, as in T. daudinii, in 

 No. 143 the first and second pairs are bent up and almost project horizontally. 

 No. 143 is figured on Plates lix. and Lx., under the heading of T. gigantea. 



Nos. 141, 160, 162, 163, 170, 171, and 181 are, in my opinion, all hybrids 

 between T. gigantea and T. elephantina. Of No. 141 we know the parents, the 

 father being the large S (49-inch) elephantina in the British Bluseum (figured 

 Pis. XLi.x., L.), and the mother the ? gigantea imported alive along with it from 

 the Seychelles {lie aux Cerjs). They vary much, but all show a condition of 

 concentric striation on portions of the scutes more or less intermediate between the 

 entirely smooth scutes of gigantea and the strongly striated scutes of elephantina. 

 All its ten specimens oi gigantea and eight of the hybrids were received alive from 

 the Seychelles. 



The ¥ ? oi gigantea are nearly always much more dome-shaped than the 6S. 



