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DESCRIPTION OP A NEW SPECIES OE GIGANTIC LAND 

 TORTOISE EROM INDEEATIGABLE ISLAND. 



By the Hon. WALTER ROTHSCHILD, PhD. 



CAPTAIN DAVID PORTER, in his Journal of a Grnhe made, in the Pacific 

 Ocean, was the first man to draw attention to the differences between the 

 tortoises of the various islands of the Galapagos group. On page 176 of the 

 1815 edition he states that Mr. Adams (the surgeon of the Essex) reported that 

 the tortoises of "Porter's Island,"/.*;. Indefatigable Island, were of extraordinary 

 size and very thick. Since that time uo one has found tortoises on Indefatigable, 

 and it was supposed they had been exterminated. In 1901 R. H, Beck found 

 a very young tortoise near the shore, and I specially urged him on his next 

 trip in 1902 to leave no stone unturned to obtain specimens of an age fit 

 to compare specifically. He, after a long and wearisome hunt, collected seven 

 specimens, two alive and five dead, the latter including a very old male of 

 gigantic size. However, the latter from old age had so nibbed and worn the 

 edges of the carajiace that I am forced to make the next largest the type of 

 the description. 



Testudo porteri sp. nov. 



Nearest allied to Testudo niyrita Dum. & Bib., but at once distinguished 

 from all other Galapagos species by its almost ciri'ular outline, the great 

 convexity of its carapace, and the ajiparent shortness in a straight line, it being 

 nearly as wide as it is long. A distinctive character also is the very large size 

 of the marginal scutes. The circular outline and great convexity of the carapace 

 give the latter the appearance of an irregular sphere cut in half. Total length 

 over curve of carapace Oil in., total width 56 in.; height of carapace 25 in.; 

 first marginal scute, mdth 7| in., length 4^ in. ; caudal scute, width 12 in., 

 length 7J in. ; supracaudal vertebral scute, width 15 in., length 9] in. ; prennchal 

 vertebral scute, width 14 in., length 9 in.; first costal scute, width 13 inches, 

 length 9| in. ; second costal scute, width 16 in., length S in. ; third costal scute, 

 length 13 in., width 7i in. ; fourth costal scute, length 10^ in., width 7^ in. 



The carapace of the type has the scutes very deeply striated, and the areolae 

 very small. The large male measirres over curve of carapace, length 68 in., 

 width 64 in. 



Il'ih. Indefatigable Island, Galapagos group. 



Named in honour of Captain David Porter, of the U.S.A. frigate Essex, 

 who first mentioned this species. 



At the present time there are known to me eleven species of Gigantic Land- 

 Tortoise from the Galdpagos Archipelago, one not yet described, and the ten 

 following : Testudo eleplmntopus, T. nigrita, T. vicina, T. tcallacci, T. portevi, 

 T. microphijcs, T. galapuyoensis, T. ephippium, T. hecki, and T. ahinydoni. 



Since describing Testudo bec/d I have received, collected by R. H. Beck, 

 five more specimens, and these show, not only that the species is really distinct 

 from T, ephijipiain, but that it belongs to a different section, as it has the third 

 ci'rvical vertebra biconvex as in T. galapiigoensis, not the fourth as in the rest 

 of tiic (ialajtagan races. 



