]:;(i ("RKTACEOIIS LAMEI.I.I HIIANCHIA. 



gerl, d'Urbignv,' but the [JostciMoi' inarii'in is more (ilili(|ni' ami the ])i)st(_MMoi' ai'ca 

 relatively .smaller. 



Bcmarlra. — The lamellar I'ilis on the postei'iur area are not mentioned l)y 

 (rOi'l)iu,ny, but attention is ealled to them by (Juerauger. 



I have seen only five specimens, which were collected l)y the late ('..). A. Mej'er, 

 and are now in the Sedgwick Museum, Cambridge. 



G. v'mdinnensis is the type of Conrad's- genus I'lichi/lluents. 



Types. — Fi'om the Cenomanian of Rouen and Le Mans. 



Dislributlun. — Cenomanian (Meyer's Beds 10 and 12) of Duuscombe, Devon. 



Cu'iiitfi — Anthonya, ir. M. iliihh, 18G4. 



(• Geol. Siirv. Ciiliroruia, Pateout.,' vol. i, ji. 181, pi. xxx, iig. 2;i().) 



Antiiony.\ ('.\ni'i.\x.\, sp. nov. Plate XIX, figs. 4, 5. 



hcxcriptinii. — Shell elongate, tajiering posteritM'ly, very inei|uilateral, much 

 eoiupressed. Anterior margin slightly convex. Ventral margin long, moderately 

 convex. Posterior margin short, truncate, forming angles with the ventral and 

 dorsal margins. Postero-dorsal margin concave. Umbones acute, near the antei'ior 

 end. A faint carina passes from the umbo to the postero-ventral angle and cuts 

 off a flattened or slightly concave postero-dorsal area. 



Ornamentation consists of numerous narrow, regular, concentric ribs over the 

 whole surface of the shell. The riljs are separated by furrows of greater width 

 than themselves. 



Measurements : 



(I) (2) 



Length . . . 34 . . -7 mm. 



Height . . . 27 . . 14 „ 



(1, 2) Folkfstoue Beils, near Coiil Pdiiit. 



Alii nil Irs. — This specie's is distinguished from .1. ( 'uniiu'liiniii ((r()rbigny)'M)y 

 the shorter anterior [larl of the sliell, the smallei- apical angle, and by the i-ibs, 

 wliicli ai-e of v(\\\:\] or nearly eipial strength over the wliole surface. It is le.ss 

 elongati' and has a siunller a[)ical angle than tlie type species A. etdlrijonitis, Cabb. 



1 Oj). cit., p. 76, pi. cclxv, figs. 1, 2; Gucrangcr, op. cil.. p. I'h pi. xvi, fig. 11. 



- 'Amer. Jouru. Couch.,' vol. v (1869), p. 47. 



3 'Pal. Frau?. Terr. Cret.,' vol. iii (1844), p. 74, pi. cclxiv, figs. 7—9 ; referrt-d to I'ti/choniija by 

 Pictet aud Campiclie, ' Terr. Grot. St«. Croix ' (' Mati'r. Pal. Suisse," ser. 4, 1866), p. 357 ; E. G. Skeat 

 ami V. Madson, "Jiir. Neoc. and Gault Boulder.s in Denmark" (' Dan marks geol. Undersiig.,' vol. ii, 

 No. 8, 1898), p. 178, pi. vi, fig. 13. 



