126 
MOLLUSCA. 
LEPTiENA. 
striae, and longitudinal, scattered spines; towards the sides and 
basal margin a series of strong, irregular ribs, with a few blunted 
and large spines; margin much indented, and irregular. 
Carboniferous Limestone, Kirby Lonsdale. 
45. Leptjena fimbriata —The Fringed Leptaena, pi. 
LIV. fig. 8. 
Producta fimbriata. Sowerby, Min. Conch. V. p. 85, pi. 
459, L Phillips, Geo. York. II. p. 215, pi. 8, fig. 11, 12. 
Oblong, nearly hemispherical; umbo large, and produced ; 
mesial furrow slight, or none; with from six to eight transverse, 
crenated furrows, the ridges spinose on their superior margin; 
lesser valve concave, and similar to the large one. 
Carboniferous Limestone, Derbyshire; Bolland ; Greenhow 
Hill; Moulton ; and Isle of Man. 
46. Lept.ena comoides. —The More-handsome Leptama, 
pi. LIII * fig. 16. 
Productus comoides. Sowerby, Min. Conch. IV. p. 31, pi. 
329. Phillips, Geo. York. II. p. 213, pi. 7, fig. 4. 
Semicircular; globose near the beak; disk much inflated; 
surface with fine, undulating stria?, and some large, shallow, lon¬ 
gitudinal furrows; hinge area flat; substance of the shell very 
thick, and rough within. 
Carboniferous Limestone, Llangaveni and Coriishead, Wales; 
and Bolland, Yorkshire. 
47. Leptaena membranagea _The Membranous Lep¬ 
tama, pi. LIII.* fig. 17. 
Leptcena membranacea. Phillips, Pal. Fos. p. 60, pi. 25, 
fig. 101. 
Semicircular, very flat, and thin ; hinge line parallel, extend¬ 
ing the whole width of the shell, and produced, with spines; 
concentrically striated; with undulating lines, among which are 
some irregular, small spines. 
Phillips mentions two varieties, viz., a, pi. 25, fig. 101 a , with nume¬ 
rous transverse lines; and b , fig. 101 b, with few transverse lines. 
Devonian Limestone, Pilton, North Devon; and South 
Petherwin, Cornwall. 
48. Leptaena aculeata. — The Spined Leptama, pi. 
LIII* fig. 36, 37. 
Productus aculeatus. Sowerby, Min. Conch. I. p. 156, pi. 
68, fig. 4. Conchiliolithus (Anomites) aculeatus , Martin, Pet. 
Derb. pi. 37, fig. 9> 10. 
Orbicular ; hinge line half the breadth of the shell; concave 
valve smooth ; convex valve gibbous, with adpressed, reflected 
spines, most numerous towards the sides, and a few' obscure, 
concentric undulations; base slightly indented. 
Carboniferous Limestone, Bakewell, Derbyshire. 
49. Lept.ena longispina —The Long-spined Leptcena, 
pi. LIV. fig. 62, 63. 
Productus longispinus . Sowerby, Min. Conch. I. p. 154, pi. 
68, fig. 1 . Productus Flemingii , lb. p. 155, pi. 68, fig. 2. 
Semicircular, broader than long; hinge line extending the 
whole width of the valves, and prolonged into large, auricular 
processes, somewhat blunted at their termination; convex valve 
with a mesial furrow ; smaller valve concave; one very long, 
round, tubular, horizontal spine, and several smaller ones, placed 
near each side in the convex valve. 
Carboniferous Limestone, Kilbride, Lanarkshire; and Moun¬ 
tain Limestone, Linlithgowshire, Scotland; and North Sunder¬ 
land. 
50. Leptena sarcinulata —The Little-truss Leptaena, 
pi. LIII* fig. 40. 
Leptcena sarcimdata. Sowerby, Sil. Syst. p. 610, pi. 3, fig. 
10 b and 12 c, and pi. 5, fig. 13. Ure’s Rutherglcn, p. 317, pi. 
16, fig. 10, 11. 
Semicircular; hinge line parallel; provided with eight or ten 
long, divaricating, simple, tubular spines; upper valve convex, 
somewhat depressed in the middle; lower valve concave; sur¬ 
face covered with numerous, very fine, radiating ribs. Length 
about half its breadth. 
This is one of the most characteristic species of the Upper Ludlow 
Limestone. 
Lower Silurian Limestone, Horderley; Cardoc, Bala, Conis- 
ton, Felindre, Horeb Chapel, &c. 
51. Lept.ena latissima —The Very-broad Leptama, pi. 
LIII* fig. 38. 
Productus latissimus. Sowerby, Min. Conch. IV. p. 32, pi. 
330. Phillips, Geo. York. II. p. 214, pi. 8, fig. 1. 
Much elongated transversely, fusiform, or convoluted; hinge 
line whole width of valves, and partially concealed by the beak; 
umbo much incurved; entire surface with coarse, longitudinal 
stria?, and many small, bristle-like spines. 
This has somewhat the appearance of L. comoides , hut is much shorter 
than that species, with the cardinal area considerably narrower. 
Carboniferous Limestone, Kirby Lonsdale; Fountains’ Fell; 
Otterburn, Northumberland; Anglesea, Wales; and the Island 
of Arran, Frith of Clyde, Scotland. 
52. Leptaena convoluta —The Convoluted Leptcena, 
pi. LIII* fig. 39. 
Leptcena convoluta . Phillips, Pal. Fos. p. 57, pi. 24, fig. 
96. 
Somewhat semicircular; hinge line the whole width of the 
valves, and extended into rounded, auriform processes; middle 
of lower valve regularly convex, with a depression between it 
and the auricles; surface with fine, rounded, numerous, longi¬ 
tudinal, divergent stria?. 
Devonian Limestone, Croyde Bay, North Devon. 
53. Lept.ena gigantea —The Gigantic Leptama, pi. 
LV. fig. 12. 
Productus giganleus. Sowerby, Min. Conch. IV. p. 19, pi. 
320. Phillips, Geo. \ork. II. p. 215, pi. 8, fig. 5, reduced. 
Transversely elongated, much inflated; hinge line nearly 
parallel, and extended into auriform processes; surface with 
irregular, undulating, radiating, obtuse ribs, covered with waved, 
unequal stria?. 
This species attains the size of nine inches in diameter. 
Carboniferous Limestone of Derbyshire; Hawes; Dent Dale; 
Northumberland; and Fifeshire. 
54. Lept.ena punctata —The Punctured Leptama, pi. 
LV. fig. 20, 21, 22, and 24. 
Productus punctatus. Sowerby, Min. Conch. IV. p. 22, pi. 
323. Phillips, Geo. York. II. p. 215, pi. 8, fig. 10. Anomites 
punctatus , Martin, Pet. Derb. pi. 37> fig. 6, 7, 8. 
Obovate; hinge line about a third less than the width of the 
shell; larger valve gibbose, with a deep mesial furrow; surface 
with concentric, wide, imbricated, laminar ridges, and furrows; 
and numerous, minute, short spines; lesser valve nearly flat, 
with shallow concentric furrows, and flattened ridges. 
Mountain Limestone, Derbyshire; Bolland; Settle; Buxton; 
Otterburn; and Cork, Ireland. 
