124 



MOLLUSCA. 



Lept^ena. 



23. LEPTiENA MARGARITACEA. — The Pearly Leptsena, pi. 

 LIII.* fig. 5. 



Producta margaritacea. Phillips, Geo. York. II. p. 215, 

 pi. 8, fig. 8. 



Suborbicular, very much inflated ; hinge line nearly parallel ; 

 beaks very large, and prominent; ears rounded; with numerous, 

 rounded, smooth, radiating striae ; with two or three spines on 

 the ears, and also on the sides. 



Mountain Limestone, Florence Court. 



24. LeptjENA Scotica — The Scottish Leptjena, pi. LIII.* 

 fig. 8, 9. 



Productus Scoticus. Sowerby, Min. Conch. I. p. 158, pi. 

 69, fig. 3. 



Semicircular; hinge line parallel, as long as the valve; umbo 

 of larger valve large, and prominent ; both valves gibbous 

 towards the beaks ; sides expanded ; convex valve with the 

 divergent striae interrupted by nearly obsolete spines, and short 

 intervening striaa, and remote, nearly parallel lines of growth, 

 which produce irregular undulations, more especially towards 

 the sides ; middle somewhat depressed ; shallow valve with 

 divergent stria;, but devoid of the spines. 



Carboniferous Limestone, Linlithgow and Arran, Scotland ; 

 and Cork, Ireland. 



25. Lept^na spinosa. — The Spinous LeptKua, pi. LIII.* 

 fig. 11. 



Productus spinosus. Sowerby, Min. Conch. I. p. 157, pi. 

 69, fig. 2. 



Suborbicular, gibbous, a little wider than long; hinge line 

 short ; convex valve with many elongated, cylindrical spines, 

 bending towards the front; concave valve destitute of spines; 

 whole surface with numerous, longitudinal stria;. 



Carboniferous Limestone, Linlithgow and Arran. 



26. Lept^ena AURiTA — The Eared Leptaena, pi. LV. fig. 

 1 and 10. 



Producta auriia. Phillips, Geo. York. II. p. 214, pi. 7, fig. 

 6,7. 



Hemispherical ; sides prolonged into prominent, rounded, 

 rugose ears, which are angular in the young condition ; surface 

 with obtuse, radiating stria;, and a few remote lines of growth. 



Mountain Limestone, Ulverston, Bolland, and Kendal ; and 

 Queen's County, Ireland. 



27. LEPTiENA scABRicuLA — The Rough Leptsna, pi. 

 LV. fig. 2, 3. 



Productus scahriculus. Sowerby, Min. Conch. I. p. 157, pi. 

 69, fig. 1. Phillips, Geo. York. II. p. 214, pi. 8, fig. 2, and pi. 

 8, fig. 20 ? lb. Pal. Fos. p. 58, pi. 24, fig. 97. Anomites 

 scahriculus, Martin, Pet. Derb. pi. 36, fig. 5. 



Nearly orbicular; hinge line parallel, and equal to the breadth 

 of the shell ; sides rather straight, producing a somewhat quad- 

 rangular appearance ; beak large, and prominent ; smaller valve 

 flat, with obscurely punctated, radiating stria-, the remains of 

 the spines producing a concentric, reticulated appearance; larger 

 valve with longitudinal, elongated, prominent, tuberculated, 

 sharp pointed striae, set in nearly quincunx order; mesial furrow 

 broad. 



Mountain Limestone, Derbyshire, Bristol, Bowes, Coalbrook- 

 dale, Harelaw, Pilton, and Brushford. 



28. Lept^na concinna The Neat Leptaena, pi. LV. 



fig. 4. 



Productus concinnus, Sowerby, Min. Conch. IV. p. 16, pi. 

 318, fig. 1. Phillips, Geo. York, IL p. 214, pi. 7, fig. 9. 



Semicylindrical ; smaller valve concave, and deeply inserted ; 

 larger one convex, concave along the middle ; neatly striated, 

 and spined longitudinally ; general surface smooth, and po- 

 lished. 



Somewhat resembling L. Martini, but smaller and smoother. 



Carboniferous Limestone, Derbyshire; Richmond and Bol- 

 land, Yorkshire ; and Cork. 



29. Lept^na quincuncialis The Squarish Leptaena, 



pi. LV. fig. 7. 



Leptana quincuncialis. Phillips, Geo. York. II. p. 214, pi. 

 7, fig. 8. 



Suborbicular ; cardinal area flat ; hinge line not so wide as 

 the valves; beak large, and prominent; sides rounded; surface 

 with strong, longitudinal ribs, alternately elevated into oblong 

 tubercles, and intersected by remote, nearly equidistant lines 

 of growth. 



Mountain Limestone, Bolland. 



30. Lept^na pustulosa. — The Pustulous Leptajna, pi. 

 LV. fig. 2. 



Leptcena pustulosa. Phillips, Geo. York. II. p. 216, pi. 7, 



%• IG. 



Nearly orbicular, but inclining to quadrate, much inflated, 

 with transverse, shallow furrows ; hinge line not so wide as the 

 valves; beak prominent, and acute; surface with some scattered 

 pustule-like, flat tubercles, which become more and more ad- 

 pressed towards the margins ; ears angular, furrowed, but des- 

 titute of spines. 



31. Leptaena spinulosa. — The Prickly Leptaena, pi. LV. 

 fig. 6. 



Productus spinulosus. Sowerby, Min. Conch. I. p. 155, pi. 

 68, fig. 3. Phillips, Geo. York. IL p. 216, pi. 7, fig. 14. 



Semicircular, compressed ; hinge line the whole width of the 

 valves ; convex valve inflated towards the beak, which is large, 

 and produced, with numerous, short spines, arranged in quin- 

 cunx order ; lesser valve concave, and spinous ; the whole sur- 

 face longitudinally striate. 



Carboniferous Limestone, Linlithgow, Bolland, and Walsing- 

 ham. 



32. Lept^na Martini Martin's Leptaena, pi. LV. fig. 



9 and 19. 



Productus 3Iartini. Sowerby, Min. Conch. IV. p. 15, pi. 

 317, fig. 2, 3, 4. Phillips, Geo. York. II. p. 213, pi. 7, fig. I, 

 and pi. 8, fig. 19. Anomites productus, Martin, Pet. Derb. pi. 

 22, fig. 1, 2, 3. 



Semicylindrical; hinge line two-thirds the width of the valves, 

 and produced; umbo very much inflated; with a flattened base, 

 and numerous, thread-like, longitudinal, spinous striae, which in 

 some specimens are furcated towards the base ; lesser valve 

 nearly flat, and deeply inserted; auricles distinct, with two rows 

 of spines. 



Mountain Limestone, Castleton, Derbyshire; Bolland; High- 

 Green- Wood; Kirby Lonsdale; Hudsewell; Harrowgate; and 

 Northumberland ; and Arran, Scotland. 



33. Leptaena laxispina The Wide-spined Leptaena, pi. 



LV. fig. 16. 



Producta rarispina. Phillips, Geo. York. p. 248, {Jim- 

 briata ? p. 215.) lb. Pal. Fos. p. 59, pi. 25, fig. 29. 



