Terebratcla. 



MOLLUSCA. 



133 



16. Terebratula Sowerbii — Sowerby's Terebratula, pi. 

 LII. fig. 35, 36. 



T. Uplicata. Sowerby V. p. 53, pi. 437, fig. 2, 3. 



Oblong-ovoid, inflated ; both valves equally convex ; beak 

 obtuse, very little incurved; sides straight, and obtuse; base a 

 little hollowed; smaller valve with two large, flat, rounded 

 plaits, gently merging into a flat furrow on both sides; surface 

 very smooth. 



Upper Greensand, Cambridgeshire. 



17. Terebratula elongata. — The Elongated Terebra- 

 tula, pi. LII. fig. 33, 34. 



T. elongata. Sowerby, V. p. 49, pi. 435, fig. 1 . 

 Oval ; valves equally, regularly, and moderately convex ; 

 beak small, acute, and slightly incurved ; surface smooth. 

 DistiDguished from T. carnea by its length. 

 Lower Greensand, Court-at-Street, and the Chalk at Norwich. 



18. Terebratula carnea The Flesh-coloured Tere- 

 bratula, pi. LIV.* fig. 30, 31, 32, 33. 



T. carnea. Sowerby, I. p. 45, pi. 15, fig. 5. Brongniart, 

 Env. de Paris, pi. 4, fig. 9- 



Subrotund, obtusely pentangular, depressed; valves equally 

 convex, slightly flattened along the middle, smooth; beak small, 

 flat ; base flat, and short ; sides plain. Diameter one inch. 



The Upper Chalk, near Norwich, contains specimens of a 

 fine flesh-colour ; also at Warminster, Devizes ; Northfleet, 

 Lewis, and Yorkshire. 



19. Terebratula Sacculus. — The Little Bag Terebra- 

 tula, pi. LII. fig. 39, 40, and pi. LV.* fig. 31. 



T. Sacculus. Sowerby, V. p. 65, pi. 446, fig. 1. Phillips, Geo. 

 York. n. p. 221, pi. 12, fig. 2. lb. Pal. Fos. p. 91, pi. 35, fig. 166. 

 Anomites Sacculus, Martin, Pet. Derb. pi. 46, fig. 1, 2. 



Obovate, gibbose ; with a broad and deep central furrow, 

 which divides the larger valve into two lobes; the smaller valve 

 has also a shallow space near the edge, from whence proceeds 

 an elevation, emanating from a minute sinus in the edge ; beak 

 small, and sharp. 



Carboniferous Limestone, Limerick, Dublin; Holland, Bristol, 

 Rutherglen, and Orton. 



20. Terebratula lata — The Broad Terebratula, pi. 

 LIV.* fig. 14. 



T. lata. Sowerby, I. p. 227, pi. 100, lower figure. 



Suborbicular, smooth, subdepressed ; length and width of 

 smaller valve about equal; larger valve subcarinated; beak pro- 

 minent, and nearly straight ; base rounded. 



Inferior Oolite, Cheltenham. 



21. Terebratula ovoides The Oval Terebratula, pi. 



LIV.* fig. 34. 



T. ovoides. Sowerby, I. p. 227, pi. 100, upper figure. 



Oblong-ovate, smooth; beak produced; larger valve gibbous, 

 and subcarinated; lesser valve convex; base a little produced; 

 sides obtusely angled, at about a third from the beak. Length 

 a half more than its width. 



Calcareous Grit, Suffolk, Scarborough, and Gristhorpe. 



22. Terebratula trilineata The Three-lined Tere- 

 bratula, pi. LIV.* fig. 15. 



T. ornithocephala. Young and Bird, p. 229, pi. 8, fig. 14. 



Ovate-rhomboidal, subdepressed ; margin very faintly undu- 

 lated ; both valves with two or three striae ; beak moderately 

 convex, and nearly straight ; base slightly produced. 



Inferior Oolite, Glazdale and Coldmoor ; Lias, Whitby. 



23. Terebratula variabilis — The Variable Terebratula, 

 pi. LIV.* fig. 19, 20, 21, 22. 



T. variabilis. Sowerby, VL p. 148, pi. 576, fig. 2, 3, 4, 5. 



Oblong, or suborbicular, rather convex, and smooth ; beak 

 considerably produced, and truncated, with the perforation 

 round, large, straight, and truncated ; internal area with a large 

 sinus. 



Common in the Red Crag, Sutton ; and the Coralline Crag, 

 Ramshot. 



24. Terebratula obesa The Swollen Terebratula, pi. 



LIV.* fig. 28, 29. 



T. ohesa. Sowerby, V. p. 54, pi. 438, fig. 1. 



Ovate, globose ; both valves regularly convex, their width 

 and depth equal to about two-thirds of the length of the shell ; 

 larger valve regularly convex to the margin ; beak short, very 

 obtuse, and incurved ; base rather obtuse, and elevated, with a 

 shallow, broad sinus in the middle ; smaller valve somewhat 

 depressed on each side of the produced base, and also near 

 the edge into the central sinus. 



Gault, Cambridgeshire. 



25. Terebratula intermedia. — The Intermediate Tere- 

 bratula, pi. LIV.* fig. 35. 



T. intermedia. Sowerby, I. p. 48, pi. 15, fig. 8. 



Obscurely-pentangular, somewhat depressed, smooth ; larger 

 valve with two depressions, and more convex than the smaller 

 one, which has three depressions ; base with moderately deep 

 undulations, which extend half way along the valves, from which 

 they are regularly convex. 



Coral Rag, Malton ; the Calcareous Grit, Castle Howard ; 

 and the Great Oolite, Weston. 



26. Terebratula subundata. — The Half-waved Tere- 

 bratula, pi. LIV.* fig. 43, 44. 



T. siibundata. Sowerby, I. p. 47, pi. 15, fig. 7- Phillips, 

 Geo. York. I. p. 94, pi. 2, fig. 25, 26. 



Nearly circular, rather depressed, smooth ; valves equally 

 convex ; base straight, or slightly depressed in the centre, with 

 a single undulation on each side of it. 



Upper and Lower Chalk, Norfolk and SuBblk; Danes Dyke 

 and Speeton, Yorkshire. 



27. Terebratula resupinata The Back-lying Tere- 

 bratula, pi. LIV.* fig. 41, 42. 



T. resupinata. Sowerby, II. p. 1 16, pi. 150, fig. 3, 4. Phil- 

 lips, Geo. York. I. p. 134, pi. 13, fig. 23. 



Oblong-ovate; beak small, slightly incurved; lower valve ob- 

 tusely carinated; base depressed by a large plait, rounded in the 

 middle ; sides elevated ; lower valve with an obtuse, broad and 

 rounded keel, and a longitudinal ridge on each side. 



Inferior Oolite, Ilminster, and the Lias, Wilton Castle. 



28. Terebratula semiglobosa. — The Nearly-globular 

 Terebratula, pi. LIV.* fig. 45, 46. 



T. semiglobosa. Sowerby, I. p. 48, pi. 15, fig. 9- Brongni- 

 art, Env. de Paris, pi. 9, fig- !• 



Nearly globular, very much inflated, smooth ; larger valve 

 deepest, and uniformly gibbous; smaller valve with two slight 

 elevations ; base undulated. 



Upper Greensand, Warminster and Tetsworth ; and Upper 

 Chalk, Danes Dyke. 



2 L 



