105 
CARDIUM  Parkinsoni. 
TAB. XLIX. 
Spec. Caar. Gibbose, rather oblique, posterior side 
' straightish; surface slightly rugose, with nearly 
forty longitudinal ribs, having slight transverse 
rising'’s on each. 
nr A 
Tus elegant shell is larger and more delicately formed 
than our Cardium edule, or any of its varieties; it is also 
less angular or acute at the posterior side; the number of 
strie is generally about thirty-six, with some differences in 
their relief. The transverse ruge, which are most promi- 
nent near the margin, are less numerous than in the common 
Cockle. The inner marginal teeth are distinctly incurved. 
I do not know of a similar Cockle in a recent state, although 
it has but few distinguishing characters: it much resembles 
Cardium maculatum, Lister 328, No. 165; from the bay 
of Campechy, which has thirty-one ribs. —* 
This very neat and perfect specimen was presented to me 
by Mr. Parkinson, who, as a sort of Volunteer in the Natural 
_ History of Organic Remains, has been so deserving of 
remembrance, that I felt it a kind of duty to give it his so 
respectable name. 
The Craigs afford some other species, but I have only 
received this from Mr. Parkinson, besides somewhat smaller 
yp 7s 1 
IY, / ! ¥ 
