PROCEEDINGS OF THE CONCHOLOGICAL SOCIETY. 65 



A few varieties included in the foregoing list not having 

 been as yet formally described, although the names have been 

 frequently made use of both in print and in ms., it will be con- 

 ducive to convenience to give descriptions. 

 Arion ater var. brunnea Rbk. 

 Animal uniform deep brown. 



This form is very distinct indeed from var. riifa^ to 

 which some writers have assigned it. — W.D.R. 

 Arion ater var. bicolor Rbk. 



Animal bright chocolate-brown on the back, brilliant prim- 

 rose-yellow on the sides, the line of demarcation between 

 the two colours being sharp and decided. 

 This is the variety which I have always spoken of as 

 the var. hicolor Moq. ; and it agrees with his description. 

 But Moquin-Tandon refers to a figure of Ferussac's as the 

 basis of his description, and Fc^russac's figure is not Arion 

 ater at all, but A. sitbftisais of typical colour. This being 

 the case, Mr. Cockerell and others have attached my name 

 to the var. bicolor as British, although I have never form- 

 ally described it. I have no objection to accepting the 

 responsibility, inasmuch as I was the first to record it as 

 British, which I did some years ago in ' Science Gossip.' 

 My own opinion, however, mclines to attributing the 

 variety to Moquin-Tandon, expressly excluding his refer- 

 ence to Ferussac's figure ; but as the question is one on 

 which great divergence of opinion is possible, it will be 

 well for the present to leave it open. — W.D.R. 

 Arion circumscriptus var. subfusca Rbk. 

 Animal brownish with dark bands. 



This is simply the brownish form which corresponds 

 to the var. siibfiisca of A. hoitensis, on which account I have 

 used the same varietal name. 

 Limax cinereo-niger Wolf. 



Some authors consider this to be merely a variety of 

 L. maximus^ on the ground that in the anatomy of the 



