418 



NOVITATFS ZOOLOGICAE XXII. 1915. 



ON THE GIGANTIC LAND TORTOISES OF THE SEYCHELLES 

 AND ALDABRA-MADAGASCAR GROUP WITH SOME 

 NOTES ON CERTAIN FORMS OF THE MASCARENE 

 GROUP. 



By lord ROTHSCHILD, F.R S., Ph.D. 



(Plates XXXIII.— LXXVI.) 



INTBODUCTIOIT 



"\T7 HEN Dr. Gunther wrote his great work on the Gigantic Land Tortoises in 

 ' » the Collection of the British Museum he was able to divide the species 

 or races into three well-characterised sections, which, in spite of certain donbts 

 raised by the snbseqnently described Testudo sumeirei Sanz., will, I believe, be 

 perfectly maintainable. These three groups were diagnosed as follows : 



Nuchal plate present; third cervical vertebra biconvex ; golar donble. 



Aldabra races 



Nuchal i>late absent ; fonrth cervical vertebra biconve.x ; gnlar donlile. 



Galapagos races 



Nnchal plate absent ; I'onrth cervical vertebra biconvex ; guhir single. 



Mascarene races • 



At that time Dr. Gunther was able to distinguish amongst the available 

 material 4 Aldabra races, Galapagos races, and 5 Mascarene races ; 15 in all. 

 Owing to the great interest shown in these creatures and the exhaustive investiga- 

 tions of many students subsequent to the issue of his book, a considerable number 

 of species or races have been added to our knowledge, and while one species has 

 had to be .sunk another has been re-established, so that now we know T well- 

 established and 'Z doubtful races of Giiuther's Aldabra Group, 13 well-defined 

 and 2 doubtful races of the Galapagos Group, and 8 well-established and 2 

 doubtful races of the Mascarene Group. As later researches have demonstrated 

 that Gunther's Aldabra Group was originally spread over Madagascar, the 

 >SeychelIes and most of tlie islands between and around, in addition to Aldabra 

 itself, I am calling this grouji here and for the future the SEYCHELIiES AXD 

 AIiDABBA-MADAGASCAR GROUP. As they now stand the groups work out 

 as follows : 



Seychelles and Aldabra-Madagascar Group. 



Testudo elephantina Dum. and JBibr. 

 Testudo daudinii Dum. and Bibr. . 

 Testudo gigantea Schwcigg. . 

 Testudo gouffei Rothsch. 

 Testudo sumeirei Sauz. . 

 Testudo grandidieri NmW. 

 Testudo ahrupla Graiulid. 

 Testudo species .... 

 Testudo Hjjecie.t . . . . 



North Aldabra 

 8onth Aldabra 



Various islands of 

 the Seychelles 



Madagascar 

 Madagascar 



? 



? 



