ANODONTA. 43 



and I suspect that the Doctor mistook this excrescence 

 for a cardinal tooth, and therefore applied the specific 

 epithet ^' dentatus/^ He omitted any mention of this 

 character in his Dithyra, when he changed the name to 

 " paludosus/^ Var. 2. Scarborough (Bean) ; Otters 

 pool, Lancaster (Tyler) ; Oxwich marsh, near Swansea 

 (J. G. J.). This is the A. ponder osa of C. Pfeiffer. 

 Var. 3. Bog of Allen, Ireland (Humphreys) ; Clumber 

 lake, Notts (J. G. J.) . It is the A. Cellensis of C. Pfeifier. 

 Var. 4. West of Ireland (Humphreys). Var. 5. E. 

 Corfe, Dorset (J. G. J.) ; ponds at Wistow in Leicester- 

 shire, Wynyard Park, Co. Durham, and Oxford (Nor- 

 man). This appears to be the Mytilus Avonensis of 

 Montagu (Test. Brit. p. 172), judging from his descrip- 

 tion and the figure of that species which is given by 

 Maton and Rackett in the ' Linnean Transactions,' vol. 

 viii. pi. 3. A. f. 4. The shell of this species is also liable 

 to be distorted; and I have a specimen in which the 

 lower part of the left valve is deeply notched opposite 

 the beak, owing to an injury of the mantle on that side, 

 the other valve being entire. 



The fry have triangular and pearly shells, which might 

 easily be mistaken for the valves of a Cypris or smaller 

 Entomostracan. The epidermis only is coloured in this, 

 as well as in the other species : the surface of the shell 

 itself, under the epidermis, is white or colourless. 



2. A. anati'na *, Linne. 



Mytilus anatinus, Linn. Syst. Nat. ed. xii. p. 1158. A. cygnea (partly), 

 F. & H. ii. p. 155, pi. xxxis. f. 3. 



Body grey, of different shades of intensity : manth bordered 

 with dark brown : foot yellowish -grey, or red : gills greyish- 

 brown. 



* Belonging to {e. g. food for) ducks, 



