118 



NUCULA impiessa. 



TAB. CCCCLXXV— /g-. 3. 



Spec. Char. Transversely oval^ depressed^ smooth ; 

 beaks near one extremity ; lunette deeply 

 sunk, convex, elongated ; edges entire. 



1 HE deep lunette, and margin regularly curved, except 

 where the lunette makes it straight, sufficiently distin- 

 guish this species. 



A silicized fossil from Blackdown. 



NUCULA antiquata. 



TAB. CCCCLXXY. —fg. 4. 



Spec. Char. Triangular, rounded, gibbose, an- 

 tiquated, longitudinally striated; lunette heart- 

 shaped, sunk ; margin toothed. 



A MORE gibbose shell than most of the analogous Nu- 

 culaB : it is rendered very uneven by its irregular mode 

 of growth ; the beaks are incurved and close together. 

 From Blackdown, cast in Silex. 



NUCULA Ovum. 



TAB. CCCCLXXVL— /g^. I, 



Spec. Char. Transversely obovate, ventricose, 

 smooth, anteriorly pointed. 



About the size of a wren's egg ; nearly as deep as 

 long ; the posterior extremity is regularly rounded, the 

 other drawn out in a short point. 



Presented by our kind friend the Right Hon. the 



