ROEBUCK : RE-ESTABLISHMENT OF I.IMAX TENELLUS. 109 



although a good conchologist, and the locahties given are not Hkely 

 ones, besides which the report includes various other improbable 

 things, so that this record of Z. tenellus may be either a mis-print or 

 an error of determination. At all events it is not proven. 



This species is omitted altogether from the current edition of the 

 Conchological Society's List, though it appeared in the former editions 

 of 1883 and 1892, in the latter case with mark of doubt, so that the 

 present record is equivalent to the addition of a new mollusc to the 

 British fauna. . 



The addition to the catalogue of British mollusca will now stand 

 as follows : — 



Limax tenellus Midler (em. Nilsson). 

 V. cerea IJeld. 

 V. fulva Norinand. 



The general distribution of L. tenellus is interesting, and fully bears 

 out the soundness of the views so ably set forth by Mr. Taylor in 

 his Monograph as to the origin and dispersal of moUuscan life. It is 

 one of the weaker forms of life which have been driven into the 

 remoter and more uncongenial regions by the more dominant forms 

 which are of higher and later development, and its range shows that 

 Central Europe is most probably the centre of origin of our molluscan 

 forms of life, and it is well known that the species which now inhabit 

 that region include the strongest and most highly developed of all 

 known to exist, surrounded on all sides by the weaker and more 

 primitively organized forms. 



Limax tenellus in Britain is in like manner driven to inhabit the 

 remote fastnesses of pine forests and perhaps heathy tracts, where the 

 higher forms which have ousted it from the best districts do not seem 

 to occur, and where it is accompanied by similarly less highly deve- 

 loped species. 



Now that L. tenellus is ascertained to be truly a member of the 

 British fauna, it would be well to have it carefully searched for, more 

 especially in the autumn, which is its main time of occurrence, and 

 on fungi, etc., in the deeper recesses of ancient pine forests through- 

 out the kingdom. 



