150 PERMIAN FOSSILS, 



Terebratulixes sufelata, Schl. Von Buch, Uebe/ Terebrateln, p. 102, 1834. 

 (?) — ,, Phillips, Encyc. Met., vol. iv, pi. iii, fig. 4, 1834. 



(?) — INFLATA „ Op. cit., p. 617. 



— SUFFLATA „ Quenstedt, Wiegmann's Archiv, 1835. 



— — » Le Cocq., Transl. Von Buch, Mem. Soc. Geol. de 



France, t. iii, pp. 213-14, pi. xix, fig. 12 bis, 1838. 



— — „ Morris, Catalogue, p. 137, 1843. 



— — ,. De Verneuil, Bull. Soc. Geol. de France, 2"" serie, 



t. i, p. 26, 1844. 



— — „ Geol. Russ,, vol. i, p. 222, 1845. 



— ELONGATA, var. ScM. Op. cit., vol. ii, p. 69, pi. ix, fig. 9 c. 



— SUFFLATA „ Tennant, Strat. List, p. 88, 1847. 



— — ,, King, Catalogue, p. 7, 1848. 



— ELONGATA „ Geinitz, Versteinerungen, p. 11, pi. iv, fig. 29 



a,b,c; fig. 32 a, b, c, &c., 1848. 



Diagnosis. — Smooth to the eye ; but microscopically granulated through being 

 crowded with minute punctures : in general five eighths of an inch long, and half an 

 inch wide : anterior half widest, and obtusely rounded : posterior half rather tapering : 

 moderately and regularly convex : rounded at the margins of the anterior half: marked 

 with rather prominent lines of growth. Large valve with a regularly-formed mode- 

 rately-sized median furrow : mnbone prominent and gibbous : foramen moderate in 

 size ; truncating the point of the umbone ; and bounded inferiorly by the apex of the 

 deltidium. Small valve regularly rounded. 



Epitliyris sufflata is not so variable as E. elongata : its variation is chiefly limited to 

 the median sinus, which, although well defined in general, is occasionally only slightly 

 indicated, as in the specimen represented in figs. 6 and 9, PI. VII. 



It is smaller and more tumid than the last species ; and so obviously distinct from 

 it, that I totally disagree with Geinitz in uniting them. It differs from Epithyris 

 elongata in having both valves more regularly rounded ; the umbone more gibbous, 

 and prominent ; the margins of its anterior half rounded, and not sharp ; the small 

 valve not ridged (but rounded) medio-longitudinally ; the lines of growth stronger ; 

 the median sinus narrower, and more obviously defined ; the posterior half not quite 

 so tapering ; and the punctures rather smaller. 



Epithyris sufflata appears to be identical with a shell found in the mountain-limestone 

 of Bolland, probably hitherto considered a variety of E. sacculus — a distinct, though 

 closely allied species. The latter differs from the former principally in having the front 

 decidedly emarginate : both appear to graduate into each other. 



Epithyris sufflata is a less common species than E. elongata. It occurs at Humbleton 

 Quarry (first noticed by Quenstedt), Tunstall Hill, Ryhope Field-House Farm, Dalton- 

 le-Dale, and Castle-Eden-Dene, in Shell-limestone ; and at the north end of Black Hall 

 rocks, in a brecciated form of a probably parallel rock ; also at Tynemouth Cliff, in 

 what appears to be a subordinate bed of breccia. The apparently identical shell. 



