1865.] TAWNET KHiETIC BEDS AND SUTTON STONE. 81 



11. Descriptions of the Species. 



1. Ammonites Suttonensis, spec. nov. 



1 am unable to describe this Ammonite, the characters of the back 

 and keel not being sufficiently preserved in my specimens. In a 

 side view it resembles A. Hettangiensis, Terquem, but it does not 

 seem to have a square and slightly keeled back like that species. It is 

 allied to A. Johnstoni or some of the ribbed " Planorbes." Diameter 

 li inch. 



Locality and position. — I have found this species about 20 ft. 

 above the base of the Sutton series, both at Dunraven and at the 

 Sutton quarries. 



2. Ammonites Dtjneavenensis, spec. nov. PL IV. fig. 1. 



This fragment of an Ammonite differs entirely from the preceding, 

 being more involute, and it is more elongated. 



Locality. — Found 30 ft. above the base of the Sutton series at 

 Dunraven. 



In form this species is aUied to A. Hagenovi (Dunker), a shell 

 which, though from the Angulatus-zone, by the disposition of its 

 lobes and saddles is entirely allied to Ceratites {vide Terquem, " In- 

 fralias de Test de France," in Mem. Soc. Geol. de France, 2nd series, 

 vol. viii. pi. X. figs. 3-5). 



3. Pecten Etheridgii, spec. nov. PL III. fig. 4. 



SheU thin, suborbicular, equilateral, slightly convex. Surface 

 with numerous shallow or flat, not very closely set, radiating ribs, with 

 very fine concentric striae. Ears large, unequal, concentrically and 

 radiatingly striated; anterior ear slightly hollowed out. Length 

 1^ inch ; breadth fths of length ; umbonal angle 70°-75°. 



Locality and position. — Sutton and Southerndown series at Sutton. 



Affinities. — This shell differs from P. calvus (Goldf.) in the ears 

 being less unequal and comparatively larger. It has much resem- 

 blance to P. Schneideri, Giebel, from the Muschelkalk, but is less 

 circular in form. 



I have named this shell after my friend Mr. Etheridge, F.E.S.E., 

 who has afforded me much help in the discrimination of the species. 



4. Pecten Suttonensis, spec. nov. PL III. fig. 3. 



Shell circular, convex, inequivalve, inequilateral. Left valve more 

 convex than the right ; at the anterior side in both valves the ribs 

 bend forwards, producing the inequilateral form. Ribs alternately 

 larger and smaller ; about twenty principal ones, between each pri- 

 mary rib a smaller, and between many of the secondaries occurs a 

 still smaller rib or carina. Ribs crossed by fine, concentric, raised 

 lines of growth, which curve downwards in crossing. In the 

 auricular regions, beyond the last rib, are broad lateral areas, 

 crossed by numerous, slightly wavy, oblique lines ; posterior area 

 the wider ; there is a steep fall from the areas by the last rib, down 

 to the ears, particularly in the more convex valve. Ears large, 

 unequal, posterior ear largest ; in the right valve the anterior ear is 



