VENUS. 243 



coasts, and of which we have examined ^ome scores in their 1 

 various stages of growth, will exhibit a memorable example 

 of that confusion of identity which sometimes obscures the 

 writings of such as depend on the collation of plates and sy- 

 nonyms only. Lister has given a very good figure, marking 

 it as English. Gmclin has admirably described it, justly 

 remarking, that it differs from V. exoleta, in being less or- 

 bicular and more convex, in having the striae more raised, 

 and in having four teeth. Pulteney and Donovan described it 

 as new, under different specific names. Maton and Rackett 

 have copied both, making it the V. lactea of Donovan, and 

 a variety of V. exoleta, likening it at the same time to 

 V. verrucosa, and V. Casina, Pennant the younger has 

 made it the V. exoleta itself. And to crown all, Mr. DilU 

 wyn has erased Gmelin's shell from the system, quoting the 

 present species as the young ofV. exoleta, as the V. lactea 

 of Donovan, as the V. excisa of Chemnitz, and as the V. Ca- 

 sina of Linne*. v t v. 



25. Venus Montacuti. MoniagiCs Venus. 



Venus compressa. Montagu, pi. 26. f. 1. 



Shell strong, thick, nearly orbicular, flat, slightly grooved 

 and irregularly wrinkled transversely, white or covered with 

 a yellowish brown skin $ inside smooth, white, with a large 

 cartilage impression near each end, the margin very flat 

 and broad, from the edge of which it becomes suddenly con- 

 vex, and is quite plain : beaks prominent, turning to one 

 side, with a small elongated heart-shaped depression under 

 them : hinge strong, with two large teeth in each valve, 

 and a transverse tooth-like ridge in one of them : diameter 

 from half an inch to an inch. 



It evidently differs from V. sulcata in not having the mar- 

 gin notched ; but we have some doubts whether it may not 

 be the young of V. Scotica. The only difference appears 

 to be, that the transverse ridges are not in that regular 

 elevated cord-like manner. 



We concur with Mr. Dillwyn, that as the specific name 

 of compressa had been preoccupied by Linne", the name of 

 him who first described it should supply its place. But as 

 all specific as well as generic names are of Latin origin, we 

 have ventured to give it a more classical termination. In 

 Y 2 the 



