DISPERSAL BY MAN. 239 



snails or mushrooms curiously before me," — and these 

 circumstances, he added, " suppose their long foreknown 

 establishment in this country, and together with their 

 general diffusion in certain soils^ incline us to consider 

 them as indigenous, and not introduced by Sir Kenelm 

 Digby for medical purposes, nor, according to Da Costa, 

 by Mr. Howard as an article of food." This conclu- 

 sion is probably a just one, but it may be observed 

 that Lister^s remarks do not at all imply that the 

 creature was admitted to English tables in early times ; 

 Da Costa understood Lister to say that the animals 

 were cooked, in the manner indicated by him, in con- 

 tinental Europe, and no doubt rightly, for the often 

 quoted remark, " Coquuntur ex aqua fluviatili, et adjectis 

 oleo, sale et pipere, lautum ferculum prseparant," 

 although a separate paragraph, follows immediately 

 upon the statement, ^' In Gallia Narbonensi admodum 

 vulgo eduntur. Item Parisiis tempore quadragesimali 

 magna quantitate vaeneunt." 



Turton's view received support, in 1839, from Forbes, 

 who, in his " Report on the distribution of Pulmoniferous 

 Mollusca in the British Isles," expressed the opinion 

 that there were good grounds for regarding the creature 

 as indigenous : " when we consider the partiality shown 

 by that shell for the newer calcareous strata in all parts 

 of Europe, and the geological correspondence of its 

 British and continental habitats, I think there can be 

 but little question of its. indigenousness ; " Gray, in both 

 his editions of" Turton " (1840 and 1857), followed the 

 view originally expressed by the author in the first 



