372 MOLLUSCA. ACEPHALA. Terebratula. 



with three long plaits ; sides with four or more plaits below the middle ; 



beak prominent Anomia striata, Ure, Ruth. 313. t. xiv. f. 6. — Ammonites 



crumena, Mart. Derb. t. xxxvi. f. 4. — Ter, erum. Sower. INIin. Conch, t. 

 Ixxxiii. f. 2, 3. — Carboniferous Limestone. 



42. T. tetraedra. — Obtusely deltoid, gibbous, plaited ; front elevated in the 

 middle, with four or five sharp plaits ; four or more sharp plaits on each side ; 

 beak rather incurved. — Sower. Min. Conch, t. Ixxxiii. f. 4.-^1 n Oolite. 



43. T. 7nedia — Very obtusely deltoid ; gibbous, plaited ; front rounded, 

 with a rising in the middle, composed of six sharp plaits ajiproaching those 

 in the middle ; beak a little incurved. — Sower. Min. Conch, t. Ixxxiii. f. 5 — 

 In Oolite. 



44. T. concinna Nearly globose ; acutely plaited ; middle elevated by 



seven plaits ; twelve or more plaits on each side ; beak projecting — Sower. 

 Min. Conch, t. Ixxxiii. £ 6 In Oolite. 



45. T. olsoleta — Nearly round, gibbous, plaited ; middle of the front a lit- 

 tle elevated by seven plaits ; sides having from seven to eleven plaits ; beak 

 projecting — Sower. Min. Conch, t. Ixxxiii. f. 7- I" Oolite. 



46. T. plicatilis. Gibbose, transversely obovate, finely and obtusely plait- 

 ed ; middle elevated by twelve plaits ; fifteen or more plaits on each side ; 

 beak slightly projecting. Soiver. Min. Conch, t. cxviii. f. 1. In Chalk. 



47. T. octoplicata. Gibbose, transversely obovate, obtusely plaited ; middle 

 elevated by eight plaits ; twelve or fourteen plaits on each side ; beak pro- 

 jecting. Sower. Min. Conch, cxviii. f. 2. In Chalk. 



48. T. Wilsord. — Circular, plaited; front cylindrical, margin acutely den- 

 tated, elevated in the middle with seven plates, nine or ten plates on each 

 side ; valves compressed towards the beaks — Sower. Min. Conch, t. cxviii, 

 f. 3. — In Carboniferous Limestone at Mordiford, E.S.E. of Hereford. 



49. T. pectita — Orbicular, gibbose, plicato-striated, with a flattish space 

 extending from the front to the beaks ; beak of the lower valve prominent, 

 slightly incurved, back of the upper valve straight, with an incurved beak. — 

 Sower. Min. Conch, t. cxxxviii. f. 1.— In Green Sand. 



50. T. Li/7-a. — Oblong, convex, with diverging fiircated plaits ; beak of the 

 lower valve greatly elongated, with two longitudinal septa, that of the up- 

 per valve short, incurved. — Sower. Min. Conch, t. cxxxviii. f. 2.— In Green 

 Sand. 



51. T. acjita — Ovato-triangular, slightly transverse ; middle elevated by 

 one large acute angular plait ; sides with one large and several small, plaits 

 each. — Smver. Min. Conch, t. cxl. f. 1, 2 Inferior Oolite. 



52. T. MajiticB — Depressed, subtrigonous ; with 10 angular plaits, half of 



them on one side elevated; upper valve convex Sower. Min. Conch. 



t. cclxvii. f. 1. — Carboniferous Limestone, Ireland. 



53. T. oi%Ma.— Depi-essed, transversely obovate, with 15 angular plaits, 

 the 5 central ones obliquely elevated from one side ; beak prominent — Sower. 

 Min. Conch, t. cclxxvii. f. 2 In Chalk. 



54. T. inconstatis — Globose, with about 26 angular plaits, half of them, on 

 one side, elevated ; beak incurved.— ^ower. Min. Conch, t. cclxxvii. £ 3, 4. — 

 Middle Oolite. 



55. T. dimidiata. — Transversely obovate, subdepressed, with a projecting 

 beak, plaited ; upper valve convex ; plaits about 30, half of wliich, on one 

 side, are elevated — Sower. Min. Conch, t. cclxxvii. f. 5.— In Green Sand. 



