July 22, 1875] 



NATURE 



239 



marie Island, the largest of the group, none were observed 

 by him, evidently because he landed here only for a few 

 hours on the south-western point. Abingdon, Binloe's, 

 Downe's and Barrington Islands were not visited by him. 

 He describes the steps of the tortoises as slow, regular, 

 and heavy ; they carry their body about a foot from the 

 ground, frequently erecting their neck, which is from 

 eighteen inches to two feet long, and very slender ; also 

 their head is comparatively small. In the daytime they 

 appeared remarkably quick-sighted and timid, drawing 

 their head into the shell on the slightest motion of any 

 object ; but they arc said to be entirely destitute of hear- 

 ing, as the loudest noise, even the firing of a gun, did not 

 seem to alarm them in the slightest degree. At James 

 Island Porter took on board as many as would weigh 

 about fourteen tons, the individuals averaging about sixty 

 pounds, that is, about 500 individuals ; and he states that 

 among the whole there were only three males which he 

 distinguished by their great size and by the greater 

 length of the tail. As the females were found in low 

 sandy bottoms, and all, without exception, were full of 

 eggs, he presumed that they came down from the moun- 

 tains for the purpose of laying ; the few males had. been 

 taken at a considerable distance from the shore, in the 

 hilly interior of the island. The eggs are perfectly round, 

 white, with a hard shell of a diameter of ih inches. He 

 found the blood of the tortoises to possess constantly a 

 temperature of 62°, whilst the general temperature of the 

 air in the Galapagos varies from 72° to 75°. 



Very significant are Porter's remarks as regards the 

 differences of the tortoises from different islands. Those 

 of Porter's Island he describes as being g.enerally of an 

 enormous size, one (not by any means the largest) 

 measuring 5^ feet in length, 4!- feet in width, and 3 feet in 

 depth. The form of the shell of the race inhabiting 

 Charles's Island is elongate, turning up forward in the 

 manner of a Spanish saddle, of a brown colour and of 

 considerable thickness, whilst the tortoises of James 

 Island are round, plump, black as ebony, and remarkably 

 thin-shelled. The tortoises of Hood's Island, one of the 

 smallest of the group, were small, and as regards form, 

 similar to those from Charles's Island. 



Twenty-two years had passed since Porter's Cruise, 

 when Darwin visited the Galapagos Archipelago in the 

 Beagle, in the year 1835. On his excursions in the in- 

 terior he still met with large individuals, but a change by 

 which the existence of these animals was much more 

 threatened than by the visits of whalers, &c., had taken 

 place. The Republic of Equador had taken possession 

 of the Archipelago, and a colony of between two and 

 three hundred people banished by the Government, had 

 been established on Charles Island, who reduced the 

 number of tortoises in this island so much that they were 

 driven by necessity to send parties to other islands to 

 catch tortoises and salt their meat. Also, pigs had mul- 

 tiplied and were roaming about in the woods in a feral 

 state, no doubt destroying the offspring of those which 

 hitherto had escaped. 



After an interval of not quite eleven years H.M.S. 

 Herald followed the Beagle on a voyage of discovery and 

 survey. The naturalist of this expedition, which reached 

 the Galapagos in the year 1846, found that the progress of 

 civilisation had been great, or, in other words, that the dis- 

 placement of the indigenous fauna by man and his com- 

 panions had proceeded apace. On Charles Island the cattle 

 had increased wonderfully, and were estimated at 2,000 

 head, beside wild pigs, goats, and dogs; the wild dogs 

 keeping the goats and pigs very much down, whilst the 

 'tortoises had been exterminated between the visits of the 

 Herald and Beagle. On the other, hand, they were met 

 with on Chatham Island, but the largest individual mea- 

 sured only two feet two inches in length. 



Recent accounts of visits to the Galapagos do not give 

 us the particulars of the present condition of the indi- 



genous fauna, nor do they contain any information as 

 regards the survivors of its Chelonians. The specimens 

 which at rare intervals reach Europe vid Panama, are 

 young individuals not exceeding twenty inches in length 

 or about twenty-five pounds in weight. The giants of 

 their race appear to be extinct or nearly so, and it is 

 scarcely to be expected that (except under most favour- 

 able conditions) any of the surviving comparatively young 

 and small individuals of so slow-growing a form of animal 

 life will be allowed, by an increasing lawless population, 

 to live long enough to reach the dimensions of the indi- 

 viduals of former generations. Therefore, there is but 

 little hope that valuable additions will be made to the 

 scanty and incomplete material in our collections ; and 

 any information as regards the present occurrence of the 

 several races in the various islands, is to be received with 

 caution, as evidently the original distribution of the races 

 has been much interfered with in the course of time by 

 the carriage of tortoises from one island to the other. 



The original condition and the fate of the tortoises of 

 the Mascarene Islands were precisely the same as in the 

 Galapagos. Their extreme abundance in the small 

 island of Rodriguez * has been referred to above. Down 

 to 1740 they continued to be numerous in the Mauritius ; 

 for Grant (" Hist. Maurit.," p. 194) writes in that year— 

 " We possess a great abundance of both land- and sea- 

 turtles, which are not only a great resource for the supply 

 of our ordinary wants, but serve to barter with the crews 

 of ships who put in here for refreshment on their voyage 

 to India." But they appear to have been much more 

 scattered in the larger islands than in Rodriguez ; and, 

 according to Admiral Kempinfeldt, who visited the latter 

 island in 1761, small vessels were constantly employed in 

 transporting these animals by thousands to Mauritius for 

 the service of the hospital. Soon, however, their number 

 appears to have been rapidly diminished ; and to the 

 causes which worked their destruction in the Galapagos, 

 here another was added, viz., widely spreading conflagra- 

 tion, by which the rank vegetation of the plains was 

 destroyed to make room for the plantations of the settler. 

 They did not long survive the Dodo or Solitaire, and 

 early in the present century the work of extermina- 

 tion was accomplished ; there is at present not a single 

 living example either in Rodriguez or Mauritius. 



Our knowledge of the indigenous fauna of the Island 

 of Reunion is still extremely meagre. If we can trust 

 to tradition, a gigantic land-tortoise once inhabited this 

 island ; and if this be really the case, it must have 

 become extinct long before the Mauritius and Rodriguez 

 species, nor is there any evidence to show its affinity to 

 one of the other races. The Seychelles do'not appear to 

 have been inhabited by these animals, certainly not within 

 historical times, all the individuals found there having 

 been imported from Aldabra and kept in a semi-domesti- 

 cated condition. 



The Island of Aldabra,' the only spot in the Indian 

 Ocean where this Chelonian type still lingers in a wild 

 state in small and gradually diminishing numbers, lies in 

 lat. 9° 25' S., long. 46° 20' E. In reality it consists of 

 three islands, separated from one another by a deep chan- 

 nel about half a mile wide. They are covered with ver- 

 dure, low tangled bushes interspersed with patches of 

 white sand ; two of the islands are rather low, hummocky 

 near the centre. The middle island is slightly the largest, 

 extending six or eight miles in length and three or four 

 miles in breadth ; it is much higher than the others, and 

 partly covered with very high trees that may be seen 

 eight or nine leagues from the deck of a moderate- size4 

 ship. 



Albert Gunther 

 {To be continued.) 



* Again amply testified by the rich collection of tortoise-bones made by 

 Mr. Slater, one of the naturalists appointed by the Royal Society tp accom- 

 pany the Transit of Venui Expedition to Rodriguez. 



