( 185 ) 



grounds he has distiiignished this new form, we find in his paper absolntely nothing 

 be3'ond the mere statement that it is different from the species previousl}' described. 

 Strictly S])eaking, the name pro])Osed by him miglit be treated as a n.omi'n inuliim \ 

 it is, certain!}', ill enough chosen. It therefore ap])eared highly desirable that the 

 specimen in the Boston Mnseum should be subjected to a thorough re-examination and 

 comparison with other races. Tbe Hon. Walter Rothschild made an application for 

 the loan of the specimen, and this was most liberally granted by the President and 

 officers of tbe Society, to whom our best thanks are due. The best return which 

 can be made to them is to show the importance of the treasure which the Society 

 possesses in this specimen. 



AVe cannot know wliether the cranial characters on which Dr. Baur is supposed 

 to have based his oiiinion, but which he has omitted to specify, are the same which 1 

 consider to be of paramount importance. But we may be quite certain that if he had 

 noticed another not less important point, viz., the singular modification of the articu- 

 lation in the vertebral column of tbe neck, he would not have failed to mention it. 



Quite at the beginning of my researches into tbe Giant-tortoises, I pointed out 

 that the flat-headed races of the Indian Ocean islands as well as of the Galapagos 

 archipelago had the fourth cervical vertebra biconvex and the third provitled with 

 a glenoid cavity behind, but that in the round-headed tortoises of Aldabra these 

 conditions were reversed. Although this observation was substantiated by the 

 examination of three individuals (it has since been confirmed by others), it seems to 

 have been passed over by subsequent observers. It is, then, a very remarkable fact, 

 that this identical modification occurs in one of the Galapagos races— viz., in Tesfudo 

 galapayoensis. This is not likely to be merely an individual variation— an exchange 

 of condyle and glenoid cavity between two succeeding vertebrae — as in both cases 

 it is the same pair of segments of the vertebral column which are modified. We 

 cannot find an exjdanation by reason of a nearer genetic relationship of the Aldabra 

 and ('harles Island races ; and equally obscure are any physiological causes which 

 might be supposed to have affected this particular pair of vertebrae ; we can record 

 it only as an additional item in the series of analogous modifications which obtain 

 in both the Mascarene and Galapagos branches of this Chelonian tyjie. 



The t^harles Island race, although at one time one of the most abundant, so 

 that as late as the year 1832 the crew of a certain frigate (? U.S. '¥. Potomac) 

 was reported to have taken 200 tortoises on a single day,* is now on the verge 

 of extinction, if its extermination has not been actually accomjilished. It is, 

 therefore, of considerable importance that any available remains which may be 

 scattered in collections should be recognised and duly jireserved. Thanks to the 

 Hon. W. Rothschild's exertions, I am able to associate on the present occasion two 

 other examples with the type in the Boston Museum. 



The first is one of two specimens in the museum of the Peabody Academy 

 of Science in Salem, Massachusetts. They are said to have been brought to the 

 United States at the same time when the two living ones were given to the Boston 

 Natural History Society, and that all of them came from Charles Island. As both 

 of these Salem si)ecimens were found to be " absolutely identical," one of them was 

 ceded to the ]{otlischild Museum. I was thus enabled to examine and comiiare 

 it directly with the Boston type. It is a cara])ace with the scutes well preserved, 

 but without other portions of the skeleton, 33 in. long in a straight line, or 

 39i in. along the median curve of the back. It is the carapace of a malr, and 



• See Baur, I.e., p. 1040. 



