(«) 



(7) 



(8) 



(9) 



UO) 



02 



GO 



57 



55 



49 mm, 



60 



GO 



56 



55 



^7 „ 



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 Avell-marked sinus. 



Measurements : 



(1) (2) (8) (1) (5) 



Length . . 76 71 67 C)7 65 

 Height . . 74 71 C>(j 65 (Hi 



(1) From the Ceuomaniau of Wiliningtou. 

 (2—10) From Wiinniuster. 



Affinities. — See P. ])exatus (p. 190). 



Bemarhs. — 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 

 aljundant in the Cenomanian of Devon.' 



Type. — From the Cenomanian of Ferte 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 Melcombe 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 Wilmino-ton. 



Pegten (Jj^QUiPECTiiN) Beaveki, tioivevhii, 1817. Plate XXXVlll. 



1817. Pecten Beavehi, J. Sowcrhy. Miu. Couch., vol. ii, p. 131, pi. clviii. 



1822. - — G. Mantell. Foss. S. Dowus, p. 127, pi. xxv, fig. 11. 



1825. — — Defrance. Diet. Sci. nat., vol. xxxviii, p. 264. 



? 1833. — — A. Gold/uss. Petref. Germ., vol. ii, p. 54, pi. xcii, fig. 5. 



— — DEPRESsus, Goldfiiss. Ibid., p. 53, pi. xcii, fig. 4. 



1837. — Beaveri, H. G. Bronn. Lethsea Geog., p. Q77, pi. xxx, fig. 19 



(ed. .3, vol. ii,pt. 5, p. 273). 



1 Pecten compositus, Sowerby (' Traus. Geol. See,' ser. 2, vol. iv, 1836, p. 342, pi. xvii, fig. 20), 

 I'roni Blackdowu, is probably a Lima related to L. cenomanensis, d'Orbigny. The type is in the 

 Bristol Museum. 



