Ammonita. MOLLUSCA. CEPHALOPODA. 243 



31. A. Herveyi Gibbose, the inner whorl two-thirds concealeil ; ribs nu- 

 merous, sharp, bi- or tri- furcated ; aperture lunate, with obtuse angles— 

 Sower. ]Min. Conch, t. cxcv — Under Oolite, near Spalden. 



32. A. Brocckii Compressed, sides hollow ; whorls 3 or 4, half concealed, 



very round, front circular, with many obtuse ridges ; aperture lunate Sower. 



Min. Conch, t. ccii — Under Oolite. 



33. A. annulata — Depressed, whorls 5 to 7i exposed, rounded ; ribs nu- 

 merous, prominent, divided on the front ; aperture roundish. — Sower, Min. 

 Conch, t. ccxxii — In Lias. 



34. A. I.amberti — Depressed, inner whorls partly concealed, front sharp 

 and crenated ; ribs strong, obtuse, bent over the front, alternately long and 



short, rarely furcate ; aperture lanceolate, short Sower. Min. Conch, t. ccxlii. 



f. 1, 2, 3. — Upper Oolite, Weymouth. 



35. A. Leachii Depressed ; inner whorls half concealed ; front sharp and 



crenated ; ribs undulated, curved over the front, often furcate ; aperture 

 ovate ; like the preceding, but more gibbous, with fewer and more promi- 

 nent ribs. — Sower. Min. Conch, t. cclxii. f. 4 Upper Oolite, Weymouth. 



36. A. omphaloides. — Gibbose, whorls increasing rapidly, inner ones half 

 concealed, front rounded, broad ; ribs prominent, waved, bent forward in the 

 middle of the front, generally furcated ; aperture transversely oblong — Sower. 

 Min. Conch, t. ccxlii. f. 5 Upper Oolite, Weymouth. 



37- A. Strangewaysi. — Discoid ; whorls 5, exposed, margin flattened, cari- 

 nated ; inner edges of the whorls obliquely flattened ; sides nearly flat, wich 



an obscure concentric furrow ; ribs twice furrowed ; aperture oblong Sower. 



Min. Conch, t. ccliv. f. 1, 2, 3. — Under Oolite, Ilminster. 



38. A. falcifer Discoid ; inner whorls half exposed, margin convex, cari. 



nated ; inner edge of the turns elevated and obtuse ; ribs numerous, curved, 

 and suddenly bent in the middle ; aperture elliptical. — Sower. Min. Conch, 

 t. ccliv. tl 2. — Under Oolite, Ilminster. 



39. A. Goodhalli — Discoid, carinated ; both edges of the whorls gradually 

 rounded ; sides nearly flat ; inner whorls two-thirds exposed ; ribs large, un- 

 dulated, irregular, obscurely tuberculated at each end ; keel very prominent, 

 thin ; ap.;rture oblong — Sower. Min. Conch, t. cclv. — In Green Sand, Black- 

 down, Devonshire. 



40. A. Kaeniffi — Discoid, convex, margin rounded, whorls (5, half exposed, 

 marginal undulations numerous ; central undulations few, very })rominent ; 

 aperture cordate, elongated — Sower. Min. Concli. t. cclxiii. f. 1, 2, 3. — Middle 

 Oolite, Kelloway. 



41. A. tripUcata — Discoid, whorls 5, exposed, with two or three oblique 

 contractions ; ribs straight, large, each divided into three as it passes over 

 the rounded front ; aperture suborbicular — Soiver. Min. Conch, t. ccxcii. 

 ccxciii. f. 4 Middle Oolite. 



42. A. biplex — Discoid, whorls 5, exposed, ribs numerous, small, obtuse, 

 split over the rounded front ; aperture oblong. — Sower. Min. Conch, t. ccxciii. 

 f. 1, 2. — In Clay, but the formation unknown. 



43. A. rotunda. — Discoid, ribs thick, numerous, split over the front, sides 

 subventricose ; aperture orbicular Sower. Min. Conch, t. ccxciii. f. 3.— 



Upper Oolite. 



44. A. decipiens. — Discoid, depressed, whorls 5, exposed, rounded on the 

 front, ribs large and few on the sides, numerous and small on the front ; aper- 

 ture orbicular — Sower. Min. Conch, t. ccxciv.— In Clay, but the formation 

 unknown. 



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