Pleuroriiynchus. 
CONCHIFERA. 
201 
C. lobatum . Phillips, Geo. York, I. pi. 9, fig. 14. 
Nearly circular, oblique ; anterior side short, with a central 
flexure, from whence it is finely rounded nearly to the beaks 
on the opposite side; surface smooth, with a few remote, 
rather regular, indistinct lines of growth. 
The Coral Rag, Mai ton, Yorkshire. 
24. Cardium semi-glabratum. —The Half-smooth Car- 
dium, pi. LXXXII. fig. 12. 
C. semi-glabratum. Phillips, Geo. York, 1. pi. 9, fig. 15. 
Transversely ovate; oblique; posterior side smooth, a little 
produced below; anterior side with longitudinal divergent stria). 
The Great Oolite, Cloughton Wyko, Yorkshire. 
25. Cardium lncertum. —The Doubtful Cardium, pi. 
LXXXII. fig. 5. 
C. incertum. Phillips, Goo. York, I. pi. 11. fig. 5. 
Slightly transverso; anterior side short and rounded ; pos¬ 
terior side largo, rounded, and slightly concave above ; beaks 
protruding: surface smooth. 
The Inferior Oolite, Yorkshire. 
20. Cardium semi-striatum. —The Semi-striated Car¬ 
dium, pi. LXXXII. fig. 9. 
C. semi-striatulum. Doshayes, Coq. Foss. I. pi. 29, figs. 
9, 10. 
Elongated ; sub-triangular; inflated ; anterior side short, 
and gently curved; posterior side concavo ; surface with the 
lower portion of the valves longitudinally striated, and a few 
faint lines of growth ; base arcuated. 
The London Clay, Bracklesham. 
27. Cardium Grcenlandicum. —The Greenland Cardium, 
pi. LXXXII. fig. 30. 
C. Grcenlandicum. Chemnitz, VI. pi. 19, fig. 198. 
Elongated; a little pointed towards the beaks, which arc 
nearly contral ; anteriorly curved; posteriorly slightly con¬ 
cave ; surface with many flattened longitudinal ribs, with nar¬ 
row intervening furrows ; the whole crossod by narrow, flat, 
circular laminae. 
The Red Crag, Bawdsey. 
28. Cardium cognatum. —The Kindred Cardium, pi. 
LXXXII. fig. 27. 
C. C'Xjnalum. Phillips, Geo. York, I. pi. 4, fig. 3. 
Nearly circular ; beaks central, much produced, and large ; 
sides nearly alike; surfaco smooth, with a few remote lines of 
growth. 
The Great Oolite, Cloughton Wyke, Yorkshire. 
29. Cardium l;evigatum. —The Smooth Cardium, pi. 
LXXXII. fig. 28. 
C. Icemgatum. Brown, Illust. Recent Conch. Gt. Brit. p. 
88, pi. 35, figs. 12-15. 
Elongated; sub-oval; somewhat oblique, and sub-com¬ 
pressed ; narrowed towards the beaks, and expanded beneath; 
surface with many flat longitudinal ribs, divided by narrow, 
shallow furrows ; the posterior side being destitute of these ; 
internal margin crenulated. 
The Pleistocene Marino Formations, Largs and Stovenston. 
Ayrshire. 
30. Cardium elongatum. —The Elongated Cardium, pi. 
LXXXII. fig. 29. 
C. elongatum. Brown, Illust. Rec. Conch. Brit. p. 88, pi. 
35, figs. 16, 17. 
Elongated ; oval; a litttle oblique; moderately inflated ; 
with numerous flat ribs, and narrow intervening furrows, 
crossed by very indistinct linos of growth ; internal margin 
with crenulations all round. 
In the Pleistocene Marine Formation, Portrush, Ireland. 
The former species ami this are nearly allied ; but this is distinguished 
by being narrower, more elongated, and more veutricose. 
Genus XXIV.—PLEURORIIYNCHUS.— Phillips. 
Shell transversely elongated ; hinge-line long, straight; an¬ 
terior side with a short prolongation ; posterior side length¬ 
ened into an acute, w f ing-shaped, auricular process ; generally 
longitudinally ribbed ; beaks but slightly produced. 
1. Pleuroriiynciius IIibernicus. —The Irish Pleurorhyn- 
chus, pi. LXXXII. figs. 14, 15. 
P. IIibernicus. Phillips, Geo. York, IL p. 210, pi. 5, fig. 26. 
Cardium Hibemicum . Sowerby, I. p. 187, pi. 82, figs. 1, 2, 
and VI. p. 100, pi. 552, fig. 3. 
Deltoidal; anterior side much produced; posterior side 
greatly truncated, and in the form of a horse-hoof; bounded 
by a large ridge, which encompasses its entire margin with a 
nearly central produced wing; beaks small, flat, and incurved ; 
wdiole surfaced with numerous sharp longitudinal ridges ; these 
on th© truncated or concave side concentrical; margins locked 
together with sharp, serrated, small crenulations. 
The Carboniferous Limestone, Limerick, Men dip Ilills and 
Dovedale, Derbyshire. 
2. Pleuroriiynciius armatus. —The Armed Pleurorhyn- 
ebus, pi. LXXXII. fig. 11. 
P. armatus. Phillips, Geo. York, II. p. 211, pi. 5, f. 29. 
Anteriorly gibbose ; slightly sub-truncate obliquely ; poste¬ 
rior sido with an elongated, slender, and acute wing ; surface 
with longitudinal, fiat, divergent ribs and furrows. 
The Carboniferous Limestone, Kildare, Ireland. 
3. Pleuroriiynciius alifoiimis. —The Wing-shaped Pleu- 
rorhynchus, pi. LXXXII. figs. 24, 25. 
P. aliformis. Phillips, Pal. Fos. p. 34, pi. 17, fig. 51. 
Cardium alwforme , Sowerby, VI. p. 100, pi. 552, fig. 2. Ib. 
Geo. Tr. 2d Scr. V. pi. 56‘, fig. 2. Goldfuss, pi. 142, fig. I. 
Sub-triangular; anterior side convex, heart-shaped, 
bounded by a carinated marginal ring ; posterior sido wedge- 
sbaped; beaks incurved; surface with many pretty strong 
longitudinal ribs. 
The Carboniferous Limestone, Bolland and Isle of Man ; 
and the Devonian Rocks, Barton and Ncw'ton. 
4. Pleuroriiynciius elongatus. —The Elongated Pleuro- 
rhynchus, pi. LXI.* figs. 29, 30. 
P. elongatus. Phillips, Geo. York, II. p. 211, pi. 5, fig. 
23. Cardium elongatum , Sowerby, I. p. 188, pi. 82, fig. 3. 
Goldfuss, pi. 142, fig. 2. 
Transversely elongated ; ventricose; anterior side elongated 
and conical; posterior sido very short, inflated beneath the 
beaks; surface with numerous fine, regular, longitudinal, radi¬ 
ating strife, which assume the form of ribs on the lengthened 
side. 
Carboniferous Limestone, Bolland, Yorkshire, and Derby¬ 
shire. 
