200 COCKEREL!. AND COLLINGE : CHECK-LIST OF SLUGS. 



apprehension as to the generic characters, and placed 



the species of Agriolitnax with which he was himself 



acquainted in Lii/iax ! 

 (5.) Megapelta, 1S57. Also founded on a misconception 



of the generic characters ; the species being known to 



the author by a drawing only. It certainly was an 



Agriolimax of the lecvis group. 

 Of the above, not one was correctly defined, nor were 

 the true generic characters mentioned, but it will be hard 

 for those who believe in strict priority to overlook them all 

 in favour of Agriolimax. Limacellus, as quoted by Kreg- 

 linger, may be safely put aside as a mistake, but I cannot 

 now refer to the place cited. The correct synonymy of 

 Limacellus seems to be : — 



(1.) Limacellus, Fer., 1S21 - Limacella, Blainv., 1817 = 



Philornycus. 

 (2.) Limacellus, Turt., 1831 = Limacella, Brard., 1815 = 



Li max. 

 There now remain four names, three of which were 

 founded solely on slugs which were doubtless species of 

 Agriolimax. In the case of Deroceras and Megapelta it is 

 true the identity is not actually proven ; but with Malino 

 there can be no shadow of doubt. Hydrolimax (or 

 Dcrocoas or Megapella) is available for the Levis group, 

 if that can be separated from the agrestis group in any 

 satisfactory manner, which I doubt. 10 

 1 20. A. agrestis. The mutations of the species are extremely 

 numerous, and according to one's opinion, have been named 

 too much — or too little. At all events, it is not difficult to 

 find several mutations not yet named, which are as distinct 

 as several of those named. Thus at Parkstone, Dorset, 

 I found four mutations, none exactly agreeing with any 

 described. Again, at Acton, Middlesex, D. B. Cockerell 

 found five specimens representing three undescribed 

 mutations, one of which was identical with one from 

 Parkstone. Of course, these mutations are but slight — 

 about equivalent in value to the band-variations of some 

 Helices. 



10 There can be little doubt, I think, but that Agriolimax should remain, seeing not one 

 of the prior genera mentioned was correctly defined. Future investigations upon the anatomy 

 of the slugs will undoubtedly necessitate the re-describing of many genera, and I would venture 

 to suggest that, instead of adopting a new term, the old one should be retained, and simply alter 

 the name of the author — e.g., should the genus Xcojanclla, Ckll., i8c)i,be found upon anatomical 

 examination to be distinct from any other genus of JaneUidee, I should retain the name 

 Neojanella, adding to it the name of the author who first adequately described and figured the 

 same. — W. E. C. 



