Mollusca of Great Britain. 373 



has been generally referred to this species, is rather a good 

 representation of the L. pereger. Indeed the L. auricu- 

 larius has not been figured in either of that author's works ; 

 and the only distinction made in the Historia Animalium 

 Anglia between the two species is by designating the former 

 " maxima." 



3. AcuTUS. 



Animal virescenti-fuscum, punctis nigris et flavis minute 



sparsum. 

 Testa elongato-ovata, ventricosa, glabra, subpellucida, ful- 



vescens, spird obliqud, acuminata. Anfractus4t. Jper- 



tura ovata. 



Long. 0.65. — Diam. 0.375. 

 a. pellucidior, striis remotis transversis. 



Plentifully in a large pool on Crymlyn Burrows, unmixed 

 with any of the other Limnei except L. truncatulus. Young 

 shells are of a more elongated form than those of either the 

 L. auricularius or L. pereger. It appears to be intermediate 

 between the two last-named species ; and I hesitated at first, 

 knowing the great variation to which this genus is subject, 

 to separate it from the L. auricularius^ to which it is closely 

 allied through its variety : but, independently of the more 

 oblique and less ampullaceous form, and of its being in- 

 variably of a thicker consistency than that shell, the cir- 

 cumstance of the two species never being found together, 

 though equally common in their respective localities, con- 

 firms me in my opinion. Besides, if they are not distinct, 

 I am convinced that no real difference will be found to 

 exist between any of the three species. 



It is admirably described and figured (Plate VII. fig. 12.) 



in 



