188 MOLLUSCA FROM THE CRAG. 
prominent, and the exterior is covered with ridges parallel to the margin, and varying 
in number from 16 to 25; these are rounded and obtuse, and rather wider than the 
spaces between them, and in many of my specimens there are the remains of coloured 
bands. In the adult shell the margin is covered with about 25—30 large crenu- 
lations. 
Amongst some specimens given to me by Sir Charles Lyell from Touraine, is a 
single valve of a shell that may probably be referred to this species, but it is not in a 
sufficiently perfect condition for a fair identification. Amongst a large number of 
specimens of our Cor. Crag shell, some may be found with the crenulated margin 
whose diameter does not much exceed half that of others in which such part of the 
shell is smooth, but the size is no argument against its having attained to a state of 
maturity. 
Astarte Bosquetii, Nyst, ‘Coq. Foss. de Belg.,’ pl. vi, fig. 16, which that author has 
doubtingly referred to 4. pygmea of Goldfuss, is probably different, and may be the 
same as A. circinnaria, Mich., it is larger and more angular than our species. Some 
specimens of 4. minuta, Nyst, brought home by Sir Charles Lyell, are also different, 
and, I think, cannot be referred to our species; the shell is smaller, more triangular ; 
the exterior is ridged, and it has a smooth margin: neither can it, in my opinion, be 
referred to our British species, 4. ¢riangularis, nor to A. parvula. 
16. Astarte Burtini, Lajonkaire. Tab. XVII, fig. 5 a—d. 
Asrarte Burrinea. Lajonk. Mém. de la Soc. d’Hist. Nat. de Par., t. i, p- 129, pl. 6a—e, 
1823. 
—- — Nyst. Rech. Coq. Foss. Prov. d’Anv., p. 8, No. 38, 1835. 
—  Bourrint. Id. Coq. Foss. de Belg., p. 160, pl. ix, fig. 7 a, 6, 1844. 
— opirauata. Id. (not Sowerby.) Id., p. 160, pl. vii, fig. 7. 
— pisrrorMts, var. 8. S. Wood. Catalogue. 
Spec. Char. Testa crassd, subtrigonuld, cordiformi, tumidd, aut compressa, subinequi- 
laterali, striatd vel sulcatd, striis obliquis ad marginem eacurrentibus ; umbonibus prominulis ; 
lunuld magna, levigatd ; margine crenulato. 
Shell thick, subtrigonal, heartshaped, tumid or compressed, slightly inequilateral, 
striated or sulcated; striae oblique, running out at the margin; umbones a little 
prominent ; lunule large, deep, and smooth; margin crenulated. 
Length, *ths of an inch ; height, *ths, nearly 
Length of var. pisiformis, +ths ditto ; height, =';ths ditto. 
Localities. Cor. Crag, Sutton, Ramsholt, Sudbourn, and Gedgrave. 
Red Crag, Sutton. 
Very abundant in the Cor. Crag, but exceedingly scarce in the Red, so much so, 
that judging from my own collection, it is doubtful if true and genuine specimens have 
been found in it. 
