532 BRITISH PALASOZOIC FOSSILS. [GastERopopa,. 
edge of the suture, and beneath it one or two smaller ones, increasing to four or five on base of body-whorl, 
which is very convex but not umbilicated. Length six lines, proportional width #, height of body-whorl +, 
height of penultimate whorl =. 
Position and Locality—Rare in the carboniferous limestone of Derbyshire. 
MurcuHISONIA SULCATA (J°Coy). 
Ref—M°Coy, Syn. Carb. Foss. Irel. t. 5. f. 10. 
Desc.—Acutely conical; apical angle 62°; spire of five gradually increasing, very convex whorls, each 
angulated a little below the middle; base very convex; umbilicus very small; mouth rounded ; surface girt with 
thick, close, subequal, thread-like ridges, the two larger of which on the angulation include the band between 
them; ridges crossed by rather strong, oblique lines of growth, very obscurely retroflexed on the band, to form 
a small sinus; about three ridges on each whorl of the spire above the band (or five altogether), and about 
thirteen on the body-whorl. Length six lines, proportional width 7%, height of last whorl 4, height of 
penultimate whorl ;;. 
The band is scarcely to be distinguished in this species, which so strongly resembles the Permian 
Turbo helicinus, that it might almost be considered a variety of it, if found in the same rock. I have 
traced on internal casts, however, the retroflexion of the lines of growth in the carboniferous shell at the most 
prominent part of the whorls, and find the corresponding lines straight and oblique in the Permian one, thus 
separating them generically. The Turbo pigmeus of de Koninck also seems closely allied, but differs apparently 
by its fewer whorls, more depressed spire, globose form, and more numerous spiral ridges. 
Position and Locality—vV ery common in the black carboniferous shales of Craige, near Kilmarnock. 
MURCHISONIA VERNEUILANA (de Kon.) Var. Kendalensis (M°Coy). Pl. 3. H. figs. 11 and 12. 
Ref. and Syn. = MW. angulata V Arch. and de Vern. Geol. Trans. Vol. VI. t. 32. f. 6. (not of Phill.) 
= M. Vernewilana de Kon. Anim. Foss. Bel. t. 38. f. 5. 
Dese.—V ery acutely conic; apical angle about 35°; spire elongate, of twelve very gradually increasing 
whorls, each strongly angulated a little below the middle by a very prominent thick band, which is either flat 
and bounded by two very fine sulci, or hollowed in the middle, leaving two thick approximate keels ; the spaces 
aboye and below the keel on each whorl nearly flat ; the former slightly wider than the latter and slightly concave, 
the latter slightly convex; base of body-whoyl very convex, evenly rounded; umbilicus very small, rounded ; 
sutures deep, simple, upper edge often slightly tumid. Surface marked with coarse, irregular, imbricating strize, 
very slightly arched sigmoidally, extending obliquely backwards to the keel above, and forwards from it below ; 
arched backwards on the band; mouth small, slightly longer than wide, ovate, angulated in the middle of the 
55 
outer edge. Length about two inches, proportional width =, height of last whorl =, height of penultimate 
whorl {£, width of mouth +, width of umbilicus 5. 
This fine species differs from the JZ. Verneuilana, as figured by M. de Koninck, only in having the band 
almost invariably a thick, undivided, flattened keel, in haying the spire slightly longer and of more numerous 
whorls, and in haying a small umbilicus. As I have observed, however, the band replaced by two keels on some 
of the upper whorls of one or two specimens, I think it best to consider the English fossil as merely a variety 
of the continental one, giving the variety, however, a distinct name for the convenience of those who may 
think otherwise. The J/. angulata Phill. is distinguished by a strong keel on each whorl below the band, 
close to the suture, and distinctly isolated on the body-whorl. 
Position and Locality—Very abundant in the impure limestone of Kendal. 
Explanation of Figures—P|. 3. H. fig. 11, natural size, back view of elongate variety; fig. 12, front 
view of, slightly shorter variety. 
