186 MOLLUSCA FROM THE CRAG. 



deeply coloured in its living condition, as in some specimens a tinge of this remains, 

 and in others there are vestiges of coloured bands. 



Sir Charles Lyell speaks of a fossil in the Miocene Deposits of America as allied to 

 this species, and a specimen in my Cabinet from Savigny very closely resembles it, and 

 is probably only a variety with the ridges rather larger, and the intermediate spaces 

 broader. 



13. ASTARTE INCERTA, S. Wood. Tab. XVII, fig. 4. 



ASTARTE PLANA. Nyst. Coq. Foss. de Belg., p. 161, pi. xi, fig. 2 a b, 1844. 



Testa orbiculato-ovatd, compressa, subincequilaterali, regulariter siriatd; natibus pro- 

 minulis; lunuld ovatd, Itsvigatd; margine crenulato. 



Shell roundedly ovate, compressed, somewhat inequilateral, regularly striated ; 

 umbo slightly prominent ; lunule ovate and smooth ; margin crenulated. 



Length, ^ths of an inch ; height, ths ditto. 



Localities. Cor. Crag, Sutton, Gedgrave. 



Belgium. 



This species is not very abundant in our Crag. As it is perfectly distinct from 

 A.plana, of 'Min. Conch.,' to which species the Belgian fossil was referred, and which 

 appears to be the same as the English Crag shell, I have proposed for it a new name; it 

 approaches very near to one of the varieties of A. gracilis, but the differences are such 

 as seemingly to justify a removal. It is natter or more compressed than any of the 

 numerous specimens of that species that I have seen, and is more inequilateral, with a 

 greater height. In the full grown shell, and in good condition, the margin is regularly 

 and deeply crenulated, differing thereby most essentially from A. plana, as also in being 

 covered with small and regular ridges. It is stated to be abundant in Belgium, where 

 it has attained to rather larger dimensions. 



14. ASTARTE CREBRICOSTATA ? Forbes. Tab. XVII, fig. 6. 



ASTARTE CREBRICOSTATA. Forbes. Annals Nat. Hist., voL xix, p. 98, pi. ix, fig. 4, 1847. 

 Jeffreys. Ann. and Mag. of Nat. Hist., vol. xix, p. 314. 

 Forb. and Hani. Hist. Brit. Moll., vol. i, p. 456, pi. xxx, fig. 9, 



1848. 

 Gray. List of British Mollusca, p. 92, 1851. 



Spec. Char. Testa ovato-trigond, compressiusculd, crassd, subinaquilaterali, postice 

 potius longiore; concentrice costatd, costis crebris odtusis, ad postice evanescentioribus, 

 margine crenulato. 



Shell ovately trigonal, slightly compressed, thick, nearly equilateral, posterior side 

 rather the longer, concentrically costated ; ribs or ridges numerous, thick and obtuse, 

 obsolete on the posterior part ; margins crenulated. 



