210 MESSRS. A. S. KENNARD .AND B. B. WOODWARD ON THE 



Balea (Turbo, L.) perversa (10). 



Nothing in the description distinguishes the currently accepted interpreta- 

 tion of: this species from the young form of one or two species of Clausilia 

 and tradition and the occurrence of undoubted specimens in the Linnean 

 collection alone support its identity. Miiller took it for the young form of 

 Clausilia rugosa, Drap., as shown by his description of the clausium (Verm. 

 Hist. ii. p. 119). We would propose to retain the name for the species 

 which has so long borne it, although Draparnaud's trivial name of fragilis 

 has been almost equally used in the past. 



*Succinea (Helix, L.) putris. 



The figure cited from Lister and the specimen in the collection leave no 

 doubt as to the identity of this species. As Hanley points out, and as already 

 noted, examples of «S. pfeifferi, Rossm., are also present in the collection and 

 it is possible that Linne did not discriminate between the two forms. 



Acrolosus (Patella, L.) lacustris. 



Although the form which to-day bears this name is not in the collection 

 whilst examples of Midler's Ancylus Jluviatilis are, we do not agree with 

 Hanley that the latter is Linne's species, but regard them as part of the 

 Miillerian contribution to the collection, since the ten individuals were 

 included in packet "No. 53." 



Linne's definition is " testa integerrima ovali membranacea, vertice mucro- 

 nato reflexo " (Faun. Svec, ed. 2, p. 534), showing that the oval shape and 

 prominent mu<u*o had struck him. Contrast this with his description of 

 Patella pellucida, which in form comes nearest to Mullet's Jluviatilis, and 

 which follows in the ' Systema' (10th ed., p. 783), where the term used is 

 " obovata." " Ovali " on the other hand is applied to elongate forms such 

 as Patella compressa and P. lutea. Then the locality " Lacubus . . . foliis 

 insidens subaquis " is more applicable to Acroloxus than to Midler's species, 

 which is chiefly found in swiftly running water, though at times the two 

 have been taken together on water plants. 



Lister's figure cited is of course more applicable to Miiller's species, as 

 also is the habitat he quotes, but in this respect Hanley's caveat (p. 6) as to 

 Linne's citation of somewhat similar figures must be borne in mind. The 

 same remark applies equally in the following. 



*Limn,ea (Helix, L.) auricularia (3). 



Linne's diagnosis " s.pira brevissima apertura ampliata " is more convincing 

 than the figures pressed into his service. These are various. Thus " Lister 

 angl. t. 2. f. 23 " seems an inflated form of L. pereger (Mull.). " Argenv. 

 conch, t. 31. f. 7. bona" shows two shells on either side of the " 7 " which 

 will pass for auricularia, whilst the one to the left of them is an inflated 



