51 



TEREBUATULA globata. 



TAB. CCCCXXXVL— /^. 1. 



Spec. Char. Subglobose; front elevated with 

 two obtuse folds, and slightly produced ; 

 surface often minutely punctated. 



A. DOUBLE sinus is formed in the lesser valve to receive 

 the elevated front of the other, whose angles are obtuse ; 

 in the young state, as is usual throughout the genus, the 

 folds or sinuses are less conspicuous ; the whole surface 

 is minutely and elegantly punctated ; in most specimens 

 the punctums are very conspicuous, but in some, whose 

 surfaces have not been at all worn, they are indistinct ; 

 and when the outer coat is worn away, they are seen to 

 unite into undulating lines: they result from the pe- 

 culiar tissue of the shell, such are often to be met 

 Avith in other species but not generally so near to the 

 surface. The lower valve is regularly convex, with 

 hardly any furrows leading from the sinuses in the front ; 

 the other valve has two slightly prominent ridges, that 

 go a little way towards its centre. 



Rather common at Nunney, nearFrome ; the Rev. J. 

 Ireland has kindly supplied specimens. 



TEREBRATULA perovalis. 

 TAB. CCCCXXXVl.— Jigs. 2 and 3. 



Spec. Char. Ovate, convex, with two elevated 

 sinuses at the front, which is depressed 

 between them ; beak incurved. 



1 HE two valves are equally convex and smooth ; the 

 margin obtuse ; the sinuses produce three very obtuse 

 ridges, two in the upper valve, and one in the front of 



