15] 
CUCULL/AEA, De Lamarcke. 
Gen. Cuar.  Bivalve equivalved, inequilateral, 
subtransverse, ventricose. Hinge rectilinear 
furnished with a series of transverse interlock- 
ing teeth, and terminated by two or three 
parallel transverse plates. Cartilage external. 
oe 
"Tus is another Genus separated from the Linnzan Genus 
Arca, and of which I presume we shall find many species. 
CUCULLAA glabra. 
TAB. LXVIL 
Spec. Cuar. Rhomboidal, anterior angle obtuse, 
posterior edge of the front rounded; surface 
covered by fine longitudinal lines decussated 
by the lines of growth: teeth of the hinge 
deeply striated. 
Syn. Cucullea glabra? Park. Org. Rem. 171. 
EEE 
Bor slightly ventricose, and without any very prominent 
angle; about one-fourth wider than long; beaks rather 
incurved; the surface to which the cartilage of the hinge 
is attached is marked with four diverging cuts, and the 
line of the hinge finely reticulated. 
These Blackdown specimens, so much externally resem- 
bling some Arca of Linnzus, help to caution us against 
