Meyer—Lower Greensand Brachiopods. Dey 
thickness occurring usually near the middle of the shell. Beak 
rather obtusely pointed or rounded in outline, and more or less 
recurved ; beak-ridges sharply defined, with a flattened, slightly 
concave, false area between them and the hinge-line. Foramen 
small, entire ; rounded above, pointed below where completed by 
the deltidial plates, which it indents. Deltidium shallow, broadly 
triangular, in two pieces, and bordered at the sides by a narrow 
depressed line. 
Valves unequally convex; the larger or dental valve much the 
deepest, the smaller valve being usually somewhat flattened towards 
the front. Socket-valve in young shells sometimes wider than long, 
in old specimens irregularly oval; surface of the valves ornamented 
by a variable number of plaits, rounded in outline, either simple or 
bifurcated, the central plaits conspicuously larger; the number on 
each valve varying from 7 to 15, usually 11. In old specimens the 
two or three central plaits on the dorsal valve are elevated into a 
mesial fold (see Pl. XI., fig. 1). The spaces between the ribs 
often exceed the width of the ribs themselves; which appears to be 
rarely the case in 7. oblonga. Lines of growth, in well-preserved 
specimens, numerous and prominent. Margins of the shell slightly 
curved at the sides, and more or less elevated in front. Loop of 
moderate length (extending nearly two-thirds the length of the 
shell), doubly attached, first to the hinge-plate, and then to lateral 
processes, which are given off at right angles by the moderately 
elevated mesial septum ; the base and, from the continual growth of 
the shell, the disused portions of these processes may be seen 
extending as a curved rib down the sides of the septum to its com- 
mencement beneath the hinge-plate. Shell-structure largely punc- 
tuated. Dimensions variable :— 
Length 74, width 5, depth 4 lines ; largest of 50 specimens. 
meee. On » 44, , 34 lines; average size. 
Localities.—This species occurs abundantly in the pebble-bed at 
Tewsley and a few other places around Godalming. In the British 
Museum there are three specimens of this shell from Dorking. 
Terebratella Fittont may be most readily distinguished from 
Terebratula oblonga, Sow, by its diminutive size, and by the 
smaller number and inequality of the plaits on either valve; it 
differs also from 7. oblonga in the ventral valve being less pointed 
towards the beak, and in the beak itself being more strongly 
recurved. In 7%. semistriata, Defr., the foramen is rounder. and of 
larger size, and the beak is more abruptly truncated. In 7. Beau- 
monti, D’ Arch., the beak is shorter and also more abruptly truncated, 
while the smaller valve is more inflated near the hinge-line. So 
much for external differences ; it remains yet to be decided, however, 
whether the loop in either of these species was doubly attached as 
in 7. Fittont. 
2. WatpHEIMIA Movutonrana, D’Orb., Pl.-XIL., figs. 12-14. 
Associated with the foregoing species there occurs a shell which, 
from its outward form and elongated internal loop, can be no other 
aD) 
yn 
