113 



PECTUNCULUS iimbonatus, 



TAB. CCCCLXXII.— /?^. 3. 



And TAB. CLYL—Jigs. 2, 3 and 4. 



Spec. Char. Orbicular, gibbose, nearly fequi- 

 lateral, longitudinally striated and obscurely 

 costated; beaks prominent, obliquely curved, 

 a lobe on the anterior side. 



J- HIS is the same shell given as a Cardium at page 128 

 of Vol. II. because the hinge had not then been seen. It 

 is distinguished from P. sublajvis just described, by the 

 prominent beaks, and smaller number of its ribs ; the 

 teeth are large in proportion to the shell, from which 

 pircumstance it should seem to be the Pectunculus men- 

 tioned as found in the Whetstone-pits by Parkinson, 

 Vol. III. p. 169. I am indebted to Mr. Good hall for 

 specimens shewing the hinge. It occurs both at Hall- 

 down and Blackdown. 



PECTUNCULUS scalaris. 



TAB. CCCCLXXII.— 7?^^. 2. 



Sp£c. Char. Obovate, convex, longitudinally 

 ribbed, ribs narrow, sharp ; area of the 

 ligament short, projecting at the extremi- 

 ties, with a triangular pit in its centre | 

 margin irregularly toothed, 



lixTERNALLY this is marked exactly in the same way 

 as P. costatus,* (lab. 27, fig. 2,) the transverse lines 

 between the ribs resembling the steps of a rope ladder. 

 The length exceeding considerably the breadth, the 

 granulated rather tlian toothed margin, and the triangular 

 pit in the hinge, ate strong marks of distinction that can- 

 iiot easily be overlooked; the teeth of the hinge are long 

 and sharp, like those of Nueula, to which genus the 

 hinge altogether bears a strong resemblance : the hinge 

 of Area aurita of Brocchi is similar. 



Sent by Miss Beminster from Hordwell; it has often 

 been confounded with Brander's Area deleta. 



* This is Area deleta of Brander, consequently it should have been 

 called Pecluuculuis deletus. 



