188 CRETACEOUS LAMELLIBRANCHIA. 
are bent nearly perpendicularly to the plane between the valves, and this narrow, 
bent portion is ornamented with close-set grooves only, placed nearly per- 
pendicularly to the line between the valves. 
Ears ornamented with radial spiny ribs. Posterior ears triangular; anterior 
ears larger —the right with a well-marked sinus. 
Measurements : 
Qe 2) 1) 4) (5) (6) C8) 19) Loy 
Length. S76) A 679167 165.162) 60) oe oo 4.9mm: 
Height . 74 71 66)%65) 66 ~ 60) 60M o6 55 eA. 
(1) From the Cenomanian of Wilmington. 
(2—10) From Warminster. 
Affinities.—See P. pewatus (p. 190). 
Remarks.—The number of lateral ribs varies to some extent, and in a few cases 
only one is found on each side of the main ribs throughout their length. 
This species is abundant in the Upper Greensand of the south of England, 
especially at Warminster. It occurs less commonly in the Chloritic Marl, but is 
abundant in the Cenomanian of Devon.! 
Type.—From the Cenomanian of Ferté Bernard (Sarthe). The specimen 
figured by Sowerby, from the Upper Greensand of Horningham near Frome, is 
in the British Museum. 
Distribution.—Higher part of the Upper Greensand of Meleombe Bingham, 
Ballard Down, Ventnor, Savernake, Maiden Bradley, and Warminster. Rye Hill 
Sand of Maiden Bradley, Rye Hill, and Warminster. Chloritic Marl of Maiden 
Bradley and the Isle of Wight. Cenomanian (Meyer’s Beds 11 and 12) of the 
Devon coast and of Wilmington. 
Prcren (Aiquivecten) Buavert, Sowerby, 1817. Plate XX XVIII. 
1817. Pecren Beavert, J. Sowerby. Min. Conch., vol. 1, p. 131, pl. elviii. 
1822. -— — G. Mantell. Foss. 8. Downs, p. 127, pl. xxv, fig. 11. 
1825. -- -— Defrance. Dict. Sci. nat., vol. xxxviii, p. 264. 
P 1833) — — A. Goldfuss. Petref. Germ., vol. 11, p. 54, pl. xcu, fig. 5. 
— — pepressus, Goldfuss. Ibid., p. 53, pl. xcii, fig. 4. 
1837. — Bravert, H. G. Bronn. Lethea Geog., p. 677, pl. xxx, fig. 19 
(ed. 3, vol. 11, pt. 5, p. 273). 
1 Pecten compositus, Sowerby (‘ Trans. Geol. Soc,’ ser. 2, vol. iv, 1856, p. 342, pl. xvii, fig. 20), 
from Blackdown, is probably a Lima related to L. cenomanensis, d’Orbigny. The type is in the 
dristol Museum. 
