184 
INOCERAMUS sulcatus. 
TAB. CCCVI. 
Spec. Char, Unequalvalved, oblong with promi- 
nent beaks, and about 9 large, longitudinal, 
plaits ; beak of one valve incurved, acute. 
Syn. Inoceramus sulcatus. Parkinson in Trans. 
Geol. Soc. vol. V. p. 59. t. 1 . f. 5. 
Birostrina costata. De Luc , MS. 
In general form this resembles the last, but it is rather 
shorter and more spatulate : it has also fewer crenula-? 
tions in the hinge : the angular folds resembling those 
of Ostrea Crista Galli are a sufficiently remarkable dis? 
tinction. 
Equally abundant with the last, at Folkstone : it has 
also been found near Lewes in Sussex. Mr. Jean 
Andre De Luc, of Geneva, has good specimens of both, 
collected at Folkstone by himself in 1797 ; but as he 
had not seen the hinge, he was induced to name the 
genus under which he placed them, from the beaks ; and 
in 1820 was so kind as to send me sketches of them 
named as above quoted : should the inequality of the 
valves prove a generic character, to distinguish them 
from Inoceramus,* or should Mr. De Luc’s name have 
been given prior to 1814, it will be right to retain it, 
and also his specific names, if they have been pub- 
lished. 
Figures 1, 2, 3, 4, and 7, are from Folkstone speci- 
mens : fig. 5 is from Lewes, collected by G. A. Mantell, 
Esq. : fig. 6 is from a clay cast found at Clophill in 
Bedfordshire : similar ones are said also to be found in 
the Campton and Southill Marl-pits, and near BeadloW 
in the same county, above the Woburn Sand, 
* The Inoceramus Cuvieri, the type of the genus, is probably an 
equalvalved shell, as I have been led to suspect by some good specimens 
I have lately examined. 
