4264 Mollusks. 



Planorbis albus. Good specimens, from Hemsworth Dam. 



„ laevis. Abundant, in one small depopulated fish-pond, 



adhering to Potamogeton crispus ; some strange monstrosities. 



„ imbricatus. Not common ; found with Velletia lacustris. 



„ carinatus. A few specimens. 



„ marginatus. Common. 



„ vortex. Common, in stagnant pools. 



„ spirorbis. Ditto. 



„ nitidus. This well-named species was common in an old 



fish-pond, among duckweed, a year or two ago, then nearly dis- 

 appeared, but has since increased. 

 Cyclas cornea. Abundant, but small. 



„ lacustris. Three specimens, obtained last year from a stag- 

 nant pool. 



Pisidiura nitidum. Common, in one small pool. 

 „ Henslowianum . Three specimens hitherto. 

 „ amnicum. Pretty common, in running streams. 



„ cinereum ? This, and pulchellum, I am not satisfied 

 about. We find here, abundantly in one locality, a species we 

 can refer only to cinereum. 



Anodon cygneus. Carted for manure last year, from Nostatt Dam. 

 I cannot speak to the varieties ; there appear to be puzzling connect- 

 ing links among them. 



Unio Pictorum. Considerable numbers in the Went, near and in 

 Went Vale. 



„ tumidus. In same locality, but not so common as the last. 

 Dreissena polymorpha. Tn the feeding canal from the Winterset 

 reservoir, attached in masses to stones, as usual, but almost every spe- 

 cimen corroded by the water. 



Charles Ashford. 

 Flounder's Institute, Ackworth, near Pontefract, 

 January 27, 1854. 



Suggestions for the consideration of Collectors of British Shells. — Might it not 

 add to the interest of collections to have well-executed figures of the animals of such 

 genera (as Arion) as have no shells, or (as Limax) as have scarcely any, so prepared as 

 to admit of being cut out of a plate and inserted in the cabinet? Perhaps the animal 

 of one species of a genus, or at least of a higher group, might be engraved and 

 coloured (in the best style) for such a purpose. It adds very much to the interest of 

 collections to intercalate woodcuts, models, or other representations of animals, which 



