ON THE NATURAL HISTORY OF 80C0TRA. 281 



Report of the Committee, consisting of Lieiit.-Col. Godwin-Austen, 

 Dr. Gr. Hartlaub, Sir J. Hooker, Dr. GriiNTHER, Mr. Seebohm, 

 and Mr. Sclater (Secretary), appointed for the purpose of 

 investigating the Natural History of Socotra and the adjacent 

 Highlands of Arabia and Somali Land. 



The balance in hand from 1870-1 (Gl. 7s. lOd.), added to the 100/. granted 

 at the York meeting, together with the amount received up to the present 

 time by the sale of tlae duplicate specimens of birds and land shells, viz., 

 171. 12-9. M., reduced by 7s. for postage, leaves a total balance in hand 

 of 1231. 13s. 2d. for any future work in Socotra or on the adjacent main- 

 land. 



Since the last report was presented, Professor I. Bay ley Balfour has 

 been working, whenever his other duties have permitted, at the extensive 

 botanical collection formed by him, to which has been added the plants 

 collected by Schweinfurth, who has since visited the island, and who has 

 placed the same most liberally at Professor Balfour's disposal. Some of the 

 preliminary diagnoses have been published, which show that the different 

 groups are very rich, and that there is a very considerable amount of 

 work in the collection, which can only be brought out slowly. Professor 

 Balfour, writing on June 17, says : — ' I ha\e a lot more diagnoses in press 

 just now, and hope in August or September to complete my work on the 

 Botany. This emeute in Egypt will, however, interfere, as Schweinfurth 

 will be unable to continue his communications, and 1 am waiting for a 

 lot of notes by him on many species. I onlj^ hope his collections will not 

 be destroyed, and as he has some of my specimens at present I am 

 somewhat anxious regarding their fate.' . . . 



The rock-specimens Collected by Professor Balfour have been worked 

 out by Professor Bonney, whose report on the subject was read before the 

 Royal Society at their last meeting of the session for 1881-2. He states 

 that the great limestone plateau, which forms so large a part of the 

 upland district of the island, is found, by the foraminifera present in the 

 rock, to be of Miocene age. This is seen to rest in many places upon a 

 floor of very ancient gneissic rock, bearing a general resemblance to the 

 most ancient rocks of North- Western Britain and other countries. The 

 Haggler mountains, forming the highest ground in the island, consist, 

 so far as is shown by the specimens brought, of granites poor in mica and 

 rich in felspar, bearing often a considerable resemblance to those of Sinai. 

 These are traversed by dykes of felsite and other igneous rocks. To the 

 south-east of this range is a tract occupied by red felsites and rhyolites, 

 with some agglomerates or conglomerates. The structure of some of the 

 former rocks renders it in the highest degree probable that they are ancient 

 lava-flows. They are anterior in date to the Miocene limestones. These 

 also are occasionally cut by basalts and perhaps by trachy tic rocks. In the 

 northern part of the island, beneath the limestone, is an argillite of un- 

 certain age, and there is probably some representative of the ' Nubian 

 sandstone.' It is, however, almost certain that for a long period anterior 

 to the Middle Tertiary, Socotra formed part of a land surface, and it is 

 quite possible that the summits of the Haggier mountains may not have 

 been even then submerged. If so, the flora, and perhaps the fauna, is 

 likely to have an exceptional interest. 



