Cytherea. 
CONCHIFERA. 
257 
1 . Terebratula virgo. —The Virgin Terebratula, pi. LIV.* 
figs. 17,18. 
T. virgo. Phillips, Pal. Fos. p. 91, pi. 35, fig. 107. 
Ovato-lanceolate; uniformly convex; beak prominent, slightly 
curved; front margin somewhat contracted, and nearly straight: 
surface with very faint longitudinal and transverse stria?, which, 
viewed through a lens, produces a beautifully reticulated ap¬ 
pearance. 
This species somewhat resembles T. hastata, but differs 
from it in the beak being more prominent, without an angula¬ 
tion, and in the curvature being so slight. 
In the Devonian Shales, Barton, South Devon. 
2. Terebratula similis. —The Similar Terebratula, plate 
LV.* figs. 8, 9. 
Sub-triangular, inflated; with three indistinct furrows towards 
the base of the valve. 
The Carboniferous Limestone, Dovedale, Derbyshire. 
3. Terebratula annularis. —The Ringed Terebratula, pi. 
LV.* figs. 01, 62. 
Sub-triangular; hinge line nearly straight, beak short; a 
broad, central, longitudinal furrow in the larger valve: whole 
surface covered with numerous divergent stria?. 
The Carboniferous Limestone, Dovedale, Derbyshire. 
1. Ostrea duriuscula. —The Rough Ostrea, pi. LIX. fig. 1. 
O. duriuscula. Phillips, Geo. York. I. pi. 4, fig. 1. 
Ovoid, compressed, with rough undulating longitudinal folia¬ 
tions . 
The Coral Rag, Malton, Scarborough. 
1 . Avicula longiaxis. —The Lengthened Axis Avicula, pi. 
LXI.** fig. 1. 
A. longiaxis . Buckman and Strickland, Geo. Cheltenham, 
p. 97, pi. 10, fig. 2. 
Valves equal; hinge line straight; anterior side much accu- 
minated ; the posterior very short: surface with fine transverse 
stria?; substance of the shell thin. 
The Lias, foot of Battledown Hill, Hewlett's Road, near 
Cheltenham. 
2. Avicula complicata. —The Complicated Avicula, plate 
LXI.** fig. 9. 
A. complicata. Buckman and Strickland, Geo. Chelt. p. 97, 
pi. 6, fig. 5. 
Hinge line somewhat oblique; the right beak short, trans¬ 
versely ribbed, and a little acute; left beak rounded; valves 
considerably twisted, and covered with longitudinal nodulous 
ribs. 
The Oolite, Lcckhampton and Crickley Hills, near Chelten¬ 
ham. 
3. Avicula longiarea. —The Long-Areaed Avicula, plate 
LXI.** fig. 14. 
Hinge line lengthened and quite straight; anterior auricle 
long, broad, and notched; posterior auricle shorter, narrow, 
and acute; valves moderately inflated; surface with longitu¬ 
dinal, rather wide, furrows, diminishing as they recede from 
the anterior side ; posterior side destitute of furrows. 
1. Gervillia acuta. —The Modiola-formed Gervillia, plate 
LXIX. fig 4. 
Gervillia acuta. Phillips, Geo. York. I. pi. 9, fig. 36. 
Lanceolate, hinge line oblique and lengthened, with a rounded 
termination; apical extremity gradually tapering; base rounded, 
surface smooth, with nearly obsolete lines of growth. 
The Great Oolite, Cloughton. 
1. Lithopiiagus antiques. —The Ancient Lithophagus, pi. 
LXXII. figs. 44, 45. 
Cylindrical; beaks blunt, surface smooth, with a few trans¬ 
verse stria? towards the umbones. 
Found embedded in a silicious mass of Asteria, from the 
Coral Rag, Malton, Yorkshire. 
1. Venus tenera. —The Tender Venus, pi. LXXXIV. figs. 
14,15. 
V. tenera. Sowerby, Geo. Tr. 2nd Ser. IV. p. 335, pi. 11, 
fig. 7. 
Somewhat lenticular; slightly transverse; beaks acute; whole 
surface curved with fine, regular, concentric stria?; lunette 
lanceolate. 
The Gualt, Folkston. 
1. Cytherea caperata. —The Wrinkled Cytherea, plate 
LXXXIV. fig. 30. 
Venus caperata. Sowerby IV. p. 31, pi. 518, fig. 1. 
Orbicular, compressed, somewhat lenticular; lunette heart- 
shaped ; whole surface covered with numerous small, rounded, 
well defined, concentric ridges; with pretty wide intervening 
ribs. 
The Greensand, Black down. 
