Mol. 53. ] JURASSIC OF THE SOUTH WALES DIRECT LINE. 731 
abundantly, Modiola scalprwm commonly, and Rhynchonella tetra- 
hedra very rarely. 
In the absence of any definite information as to the vertical 
succession of these three types of limestone, we are inclined to think, 
from their similarity to beds in the series below (Capricornus-Beds), 
that the sandy beds, with dAvicula tnwequivalvis, Cucuilea sp., and 
Ammonites capricornus, occur at the base of the limestone-beds ; 
while there seems no doubt that the ferruginous beds with Pecten 
wquwalvis and Modiola scalprun (the Marlstone) occur at the top. 
As no ammonites occur in the ferruginous beds, they can only be 
doubtfully assigned to the Maryaritatus-Zone, from analogy with 
other districts. 
Adopting this succession, the following is a list of the fossils that 
we have collected trom these beds, assigned to their different matrices, 
arranged in descending sequence :— 
( Belemnites aff. iminsterensis, Phil. 
| Pecten equivalvis, Sow. 
Pecten sp. 
(ii) The Marustone. Modiola scalprum, Sow. 
{? Zone of Ammonites margari- + Gryphea cymbium, Law, 
tatus. ) | Cardium truncatum, Sow. 
Cypricardia sp. 
Rhynchonella tetrahedru, Sow. 
\ Pentacrinus sp. 
Cit)? OSTERAISED 52 cil ce aces { Ostrea trreguiaris (?) Minst. 
: Cardinia Listeri, Sow. & mutations. 
( Ammonites (.Amblycoceras) capricornus, Schloth. 
Avicula (Oxytoma) ineguivalvis, Sow. 
| Cucullea sp. 
(1) Sandy limestone-beds. | Gervillia sp. 
{? Zone of Ammonites capri- « Goniomya sp. 
COrNUs. ) Pecten sp. 
Pinna folium, Y. & B. 
Plewromya costata, Y. & B. 
\ Unicardium cardioides, Phil. 
Paleontological Notes. 
In the sandy limestones :— 
Pecten sp. has already been alluded to as a small smooth Pecten 
of the calvus-type, but somewhat more convex. No complete 
specimens have been seen, though it is abundant in fragments. 
Avicula nequivalvis is of the typical form named sinemuriensis 
by Oppel ; it is extremely abundant. 
Cucullea sp. is very characteristic of this bed, and a chance 
fracture of a large block may reveal as many as fifty specimens 
completely covering the surface. In size and contour it seems to 
differ from any form previously figured. The nearest figure is that 
of C. bilineata, Moore, but the hinge-line in our species is much longer 
and the radial striz are never obvious, even in young forms. 
In the Marlstone :— 
Pecten sp. is a large Pecten, with both the ribs and the intermediate 
spaces sharply angular. This may be a mutation of P. equivalvis, in 
