British Association for the Advancement of Science. 131 



Next was read a Report on the distribution of the Pulmonife- 

 rous Mollusca in Britain, and the causes influencing it; drawn 

 up at the request of the Association, by Mr. E. Forbes. The 

 object of this inquiry was to ascertain the geographical and geo- 

 logical distribution of pulmoniferous mollusca in the British isles. 

 The subject was considered under three heads ; first, a view of 

 the various influences which affect their distribution ; second, a 

 detailed view of the distribution of the indigenous species in the 

 various provinces of Britain ; and third, the relations of that di- 

 vision of the native Fauna to the Fauna of Europe, and the dis- 

 tribution generally of the more remarkable species. 



Mr. J. E. Bowman exhibited specimens of a species of Dod- 

 der, Cuscuta epilinuni, first found in Britain two years ago, by 

 himself; and again in a new locality within the present month. 

 He believes it is found exclusively on flax, and has been mista- 

 ken for C Europea, from which however it is quite distinct. 



A paper was read on the cultivation of the Cotto?i of commerce, 

 by Major General Briggs. The objects proposed in the paper, 

 are, 1. To excite inquiry on the various species of cotton plant 

 that produce the cotton of commerce. 2. To ascertain the na- 

 ture of the soils adapted to each. 3. To prove the practicability 

 of cultivating the plant in India, for the supply of the British 

 market to any extent. Of the species that produce the various 

 cottons of commerce, we have at present very little accurate 

 knowledge, and this has arisen from the alterations undergone by 

 the plant in the process of cultivation. But there can be no 

 doubt that the plants which produce cotton in America, Asia and 

 Africa are of decidedly different species. The plant that produ- 

 ces the Brazil cotton, probably the Gossypium hirsutuni, grows 

 15 or 20 feet high, is perennial, and produces cotton with a long 

 and strong staple, and moderately fine and silky. The plant 

 common to the West Indies, (said to have been imported from 

 Guiana,) is triennial, bearing abundantly a fine silky long staple, 

 and is the G. Barhadense of botanists. This also is the plant 

 which produces the Sea-island cotton. When this plant was 

 carried from the coast into the interior of Georgia and Carolina, 

 the seed changed from a black to a green color, and the staple 

 became shorter, coarser and more woolly. This plant was after- 

 wards introduced into Egypt, and is the same that produces the 

 Bourbon cotton, cultivated by the French on that island. Mr. 



