GaAsTEROPODA. | LOWER PALAZOZOIC MOLLUSCA. 293 
Murchisonia scalaris (Geol. Journ. Vol. V. t. 1. f.2), which he there says is a common Bala species, recognized by 
its elongate shape, &c.; and perfect specimens of the exterior of which, he says, shew the fine striee curving back 
to the keel; but as the carinated species I have seen from Bala are quite different from the present, and agree 
with the above figure in the elongate form, so different from the present shell, which also has strong spiral striz, 
not said to exist in the JZ. scalaris, nor in the Bala forms which I have seen, I conceive this to be a perfectly 
distinct species. 
Position and Locality—tIn the Upper Bala rock of Alt yr Anker, Meifod, Montgomeryshire ; abundant in 
the Caradoc sandstone of Mulock Quarry, Dalquorhan, near Girvan, Ayrshire. 
Explanation of Figures.—PI. 1. L. fig. 20, natural size ; fig. 20 a, portion of surface of ditto magnified. 
MURCHISONIA CINGULATA (Lis. Sp.) 
Ref.—Id. Hisinger, Leth. Suec. t. 12. f. 6. 
Sp. Ch.—Very elongate, conical ; apical angle 15°; whorls about twelve, very slightly convex (less than in 
the above figure); sutures simple, or with a very slight thread-like prominence of the upper edge; band about 
one line wide, flat, smooth, scarcely defined, rather more than its own width above the suture; strize rather 
distant, delicate, arching back to the band with a slight curve. Length about two inches eight lines, propor- 
tional width +, length of last turn =. 
This large species is not likely to be confounded with any other that I know of, from its size, inconspicuous 
band, and slight convexity of the whorls. Mr Salter confounds it (Mem. Geol. Surv. Vol. IT. part 1. p. 857) 
with the little Chemnitzia sinuosa (Sow. sp.), which has an entirely different striation and has not the band of the 
present genus. 
Position and Locality —Aymestry limestone, Aymestry, Herefordshire; Pentamerus limestone of Leint- 
wardine, Shropshire. 
MURCHISONIA GYROGONIA (JM‘Coy). Pl. 1. K. fig. 43. 
Sp. Ch.—Acutely conical ; apical angle 45°; spire of three and half whorls, very strongly angulated in the 
middle by the projection of an acute carina, the upper and under sides of the volution being flat and steeply 
inclined ; sutural angle 70° to 75°; body whorl rounded below, with an additional fine keel about half way 
between the principal one and the anterior end, which is almost hid by the suture on the spiral whorls; surface 
(when preserved) marked with sharp strize, which on the upper part of the whorl extends from the suture 
obliquely backwards to the keel, curving in the opposite direction below the keel. Length four and half lines, 
proportional length of last whorl =, width 4. 
This is most allied to the Murchisonia perangulata (Hall) of the Bird’s-eye limestone of the New York 
series, but is distinguished by the shortness of the spire in proportion to the body whorl, and by the ad- 
ditional keel below the band on the last turn. It is also closely allied to the M. pulchra (M°Coy, Sil. Foss. 
Trel. t. 1. f. 19), but is on comparison found to be distinet by the fewer, longer, and more produced whorls of the 
spire. 
2 Position and Locality.—Very abundant in the fine sandy schists of Yspatty Evan, N. Wales; also in the 
calcareous strata W. of Llanfechan, Montgomeryshire. 
Explanation of Figures.—P\. 1. K. fig. 43, natural size, from the schists of Yspatty Evan; fig. 43a, 
magnified. 
Murcuisonta Luoypr (Sow. Sp.) 
Ref. = Pleurotomaria id. Sow. Sil. Syst. t. 8. f. 14. 
Sp. Ch.—Acutely conical ; apical angle about 55°; spire of about four whorls; sutural angle about 60° ; 
whorls convex, most prominent in the middle, where the band forms a prominent square keel ; between this and 
the simple suture are two thin, thread-like ridges on each whorl, and below it on the body whorl are six or seven 
similar ones about a line apart, only one of which is visible on the spiral whorls; base imperforate; entire 
