172 
CONCHIFERA. 
Modi ola. 
anterior one small and terminal ; the mantle muscular im¬ 
pression irregular, and destitute of a sinus. 
1. Modiola semi-sulcata. —The Semi-furrowed Modiola, 
pi. LXXII * fig. 17. 
M. (?) semi-sulcata. Murchison, Silur. Syst. pt. II. p. GIT, 
pi. 8, fig. 6. Cypricardia semi-sulcata. Phillips, Pal. Foss. pi. 
17, fig. 57. 
Shell transversely ovate, convex, sub-bilobate ; anterior 
considerably smaller than the other ; beaks prominent, 
near the anterior extremity ; surface covered with transverse, 
irregular, concentric furrows; length one inch, width two 
inches. 
Found in the Lower Ludlow Rock at Shelderton Ilill, and 
near Aymestry. 
2. Modiola antiqua. —The Ancient Modiola, pi. LXXII.* 
fig* 8. 
M- antiqua. Murchison, Silur. Syst. pt. II. p. 628, pi. 13, 
fig. 1. 
Shell obliquely ovate, somewhat convex, almost smooth, 
with a few nearly obsolete concentric wrinkles ; anterior lobe 
rather indistinct; beaks small, placed near the anterior side ; 
length three-eighths of an inch, breadth six-eighths. 
Found in the Wenlock Shale, at Glass-House Hill, east 
flank of May Hill. 
3. Modiola funata. —The Buried Modiola, pi. LXXI. 
figs. 12, 13. 
M, arcuata. Williamson’s MSS. 
Transversely oblong-ovate; hinge-line arcuated; beaks 
very blunt; surface with wrinkled lines of growth. 
Coal Shale, Wakefield. 
4. Modiola Williamsoni.— Williamson’s Modiola, pi. 
LXXI. figs. 24*, 25. 
M. elongata. Williamson's MSS. 
Much elongated transversely, narrow, compressed ; anterior 
side short; posterior side greatly elongated ; umbones de¬ 
pressed and blunt; surface with slightly wrinkled lines of 
growth. 
The Coal Shale, Wakefield. 
5. Modiola depressa.— Tho Depressed Modiola, pi. 
LXXII. fig. 41. 
M. depressa. Sowerby, I. p. 29, pi. 8, three upper figures. 
Ovate ; breadth nearly twice and a-lialf its length ; greatly 
depressed, and narrowing towards the posterior side ; margin 
even and very regularly curved, much so at tho anterior side; 
beaks rounded ; surface smooth and shining, and pearlaceous 
within. 
The Lower Greensand, Atherfield, Isle of Wight. 
6. Modiola pallida, —The Pale Modiola, pi. LXXII. 
fig. 40. 
M. pallida. Sowerby, I. p. 30, pi. 8, three right-hand 
lower figures. 
Oblong; breadth about twice its length : gibbose; inferior 
margin straight; posterior side slightly inflated; beaks ob¬ 
tuse ; surface smooth, and somowhat glossy. 
The Portland Stone, Fonthill and Brora. 
7. Modiola vis. —Tho Smooth Modiola, pi. LXXII. 
fig. 37. 
M. Icevis. Sowerby, I. p. 30, pi. 8, left-hand figure. 
Sub-triangular; breadth not quite twice its length ; convex; 
posterior and lower margin nearly straight; posterior side a 
little produced, united by a short curve ; beaks small ; surface 
very smooth ; the lines of growth nearly obsolete. 
The Lias, Lyme Rogis, near Weymouth, Dorsetshire. 
8. Modiola elegans. —The Elegant Modiola, pi. LXXII. 
fig* 7. 
M. elegans. Sowerby, I. p. 31, pi. 9, left-hand upper figure, 
middle and lower figures. 
Oblong, gibbose; breadth about twice its length, moderately 
convex; lower margin straight, dentated, with transverse 
furrows; posterior side inflated, with a few transverse furrows 
near the base; beaks slightly curved, and with fine, close, 
slightly undulating strhe, which pass over the most prominent 
portion of the surface, and diverge over the anterior side to 
tho base, where they become obsolete; interior frequently 
pearlaceous. 
The London Clay, Bognor and Highgate. 
0. Modiola Aldami. —Aldam’sModiola, pi. LXXII. f. 17. 
M. aspera . (?) Var. Phillips, Geo. York, I. pi. 11, fig. 9. 
Elongated ; anterior side narrow; posterior side large and 
rounded; hinge-line nearly straight and rather lengthened; 
umbones small and obtuse; surface with numerous fine stria?. 
The Inferior Oolite, Blue Wick, Glaizedale. 
10. Modiola plicata. — The Plicated Modiola, pi. 
LXXII.* fig. 1. 
M. plicata. Sowerby, p. 87, pi. 248, fig. 1. 
Much elongated transversely, its length about a fifth of its 
width, a little curved; anterior side separated by a ridge, above 
which it is striated, the striao becoming gradually obsolete 
towards the beak, where strong oblique plications commence 
divergent from tho beaks ; the other parts of tho shell smooth ; 
but with a few irregular lines of growth ; back almost straight ; 
anterior side a little truncated, and tho posterior obtuse. 
The Fuller’s Earth, near Radstock, and the Inferior Oolite, 
Cots wold Hill. 
11. Modiola imbricata. —The Imbricated Modiola, pi. 
LXXII. fig. 36. 
M. imbricata. Sowerby, 111. p. 21, pi. 212, fig. 13. 
Oval, elongated, its breadth twice its length ; front con¬ 
cave; anterior lobe forming a slightly elevated ridge, extend¬ 
ing to the beak, which is angular; surface with imbricated 
ridges. 
Tho Lower Greensand, Pulborough, and the Cornbrash, 
Felmersham. 
12. Modiola Hillana. —Dill’s Modiola, pi. LXXII. f. 8. 
M. Hillana. Sowerby, III. p. 21, pi. 212, fig. 2. 
Elongated ovate, its width a little more than twice its 
length, depressed; posterior side narrow; posterior lobe ob¬ 
scure; front a little concave; back carinatod, and tapering 
towards the beaks, which aro but slightly prominent; surface 
concentrically striated. 
The Fuller’s Earth, Bathford Hill. 
13. Modiola aspera. —The Rough Modiola, pi. LXXII. 
figs. 13, 14. 
M. aspera . Sowerby, III. p. 22, pi. 212, fig. 4. 
Ovate, transversely elongated ; length half its width ; pos¬ 
terior side acute, very gibbose ; posterior lobo obscure, small, 
and pointed ; surface with numerous transverse, elevated, rough 
stria), which are strong towards the broader side of the shell, 
