42 
species by longer, more oval shape, and carina down its larger 
valve, and its beak, though overhanging the dorsal valve, is 
separated further from it, and shows the deltidial plates. 
Our species has generally been classed as variety of Tereb. 
perovalis and also of T. globata, but is really more distinct 
from these than from the other species I have mentioned. 
From the first by its circular shape, conspicuous elevated 
biplications and incurved beak; while T’. globata is best known 
from it by having its beak so distinctly separated from the 
umbo, and showing the deltidial plates so clearly. 
Terebratula pisolithica, as its name implies, occurs in the Pea 
Grit or Pisolite, (Murchisone zone) and I have it from Leck- 
hampton, Crickley and Birdlip hills, also Selsley hill, near 
Stroud. Really good specimens are scarce, for, though not 
uncommon, it is frequently somewhat crushed. 
RAYNCHONELLA HAMPENENSIS, S. Buck. Plate ITI, fig. 6a, b, c. 
Rather wider than long; beak acute, incurved; foramen sepa- 
rated from the umbo by a slight portion of the deltidial plates ; 
valves unequal, the dorsal being larger and more tumid than the 
other ; seven to eight plaits each side of the fold, six to seven on 
the fold, which is slightly elevated, and leaves a certain well 
defined but not deep sinus in the larger valve; sinus extends 
only about half way up the valve; beak ridges fairly well 
defined, with a shallow false area. 
This species is most nearly allied to Rhynchonella concinna, 
Sowrrsy, from the Great Oolite and Cornbrash. It is dis- 
tinguished however by having fewer plaits, which are 
consequently larger. It is also less tumid, rather broader, 
the two valves are more nearly of a similar convexity, and the 
beak is more produced and incurved, and generally, if not 
always, has the foramen, which is small, surrounded by the 
deltidial plates. From Rhynch. subtetrahedra* it is distinguished 
by greater depth, a regularly distinctive raised fold, instead of 
a gradual slope. 
* The type form figured by Davipson, Brachiopoda, Plate XVI, fig. 9. 
Several other forms occurring in the Inf. Oolite are frequently confounded 
with this, and hence error in discrimination might arise. 
