TRANSACTIOiXS OF SECTION E. 721 



issued is practically a zoological monograph of the islands. A large number of 

 plane-table and theodolite observations were made, and many anthropological 

 data collected. A large scale-map was in process of construction from the plane- 

 table sheets when these and the instruments which were being employed in the 

 work were ]nirloined during repairs to the author's house by some unknown 

 workman. Their loss was not detected for some weeks, but since then every 

 effort has been made — not yet hopelessly — to recover them ; in the meantime it is 

 impossible to proceed further with the construction of the map. As the inclusion 

 of the historical and anthropological data would have rendered the Tolume too 

 bulky, they have been reserved for publication elsewhere. 



No new mammals were obtained by the expedition, but specimens of the 

 interesting wild ass, which proves to be the Nubian and not the Somaliland 

 species, were obtained. The domestic cattle, a very beautiful diminutive breed, 

 would seem to be here a long-isolated colony of the Bos longifron^, introduced 

 probably from Egypt before the Christian era. Sixty-eight species of birds are 

 now known from Sokotra, of which the expedition added ten species, four of them 

 new to science and six not previously known to live there. From Abd-el-Kuri, 

 from which no collections had previously been brought, twenty-two species, three 

 of them new to science, have been recorded. Of reptiles, Mr. Boulenger has 

 enumerated twenty-eight species, of which seven are new. Mr. E. A. Smith 

 has described sixteen new species of MoUusca, and Mr. Pocock eighteen of 

 spiders and scorpions. Six species of Crustacea are reckoned as new by Mr. A. 0. 

 AValker in quite a small shore-collection from Abd-el-Ivuri. AmoEg the Insecta 

 a large number have proved to be new endemic species. Mr. Kirby has described 

 twenty-seven among the Ilymenoptera, Mr. Gahan twenty Coleoptera ; Mr. Grant, 

 Lord Walsingham, and Sir George Hampson have enumerated twenty-seven Lepi- 

 doptera, Miss Ricardo twelve Diptera, Mr. Maclachlan three Nemoptera, and 

 Mr. Burr six Orthoptera. Mr. Pocock has described five new Myriapoda. 

 Professor I. Bayley Balfour undertook the examination of the botanical speci- 

 mens, which consisted of living plants, bulbs, tubers, seeds, and Herbarium. 

 Ijittle new was to be expected among' these after the thorough manner he had 

 himself investigated the island ; but he has found they include four species new 

 to science, and six, otherwise known, new to the flora. The whole of the plants 

 from Abd-el-Kuri — seventj^-eight in number — are recorded here for the first time, 

 and of these three are new to science, and all but .six occur on Sokotra. 



The geology, as illustrated by the specimens collected by the expedition in 

 these two islands, has been described by Professor Gregory. 



In all, over 150 species have been added to the zooloay of the islands. 



In conclusion, the institutions concerned in the expedition desire to express 

 their warmest thanks to the Council of the British Association as well as to the 

 Royal Society and the Eoyal Geographical Society for the assistance and 

 encouragement they gave to the expedition. 



5. On the Origin of Adam's Bridge. Bg J. Lomas, A.R.C.S., F.G.S 



Stretching across from the nortli part of Ceylon to the south-east coast of India 

 lies a remarkable chain of low-lying islands and shallow banks known as AdamV 

 Bridge. Rameswarain Island forms the most westerly link of the chain and is 

 only separated from Tonitoray Spit (India) by Pambam Straits, a shallow natural 

 opening which has been deepened in parts by man. Manaar Island, at the extreme 

 east of the bridge, lies close to the north-west coast of Ceylon. Between these a 

 number of smaller islands complete the chain. North of Adam's Bridge extends 

 Palk Bay, a shallow mud-floored almost currentless sea, and to the south the Gulf 

 of Manaar stretches aa a low platform, deepening fairly evenly to the south at about 

 the rate of one fathom in two miles to twenty fathoms, after which it sinks more 

 rapidly to great depths. The platform consists of sands, which in places have been 

 cemented in situ into calcareous sandstones or calcretes chiefly by the agency 

 of Polyzoa and NuUipores. These masses pi solid rock, known as 'paars,'are 



1903. "3 A 



