540 BRITISH PALALOZOIC FOSSILS. [GastTERopopa. 
STRAPAROLLUS Noposus (Sow. Sp.) 
Ref. and Syn. = Euomphalus nodosus Sow. Min. Con. t. 46. 
Dese.—Discoid, of five to six gradually increasing whorls, the spire slightly depressed below the body-whorl, 
upper surface with a strong prominent keel, which runs along nearly in the middle of the spiral whorls, and from 
which the surface slopes to the simple suture; periphery and under side of the whorls very convex, regularly 
rounded, without keel; a row of very large, obtuse, irregular tubercles or nodular swellings runs along a little 
within the middle of the under aspect of the body-whorl, nearly concealed by the suture on the whorls of the 
spire; these tubercles are irregularly unequal in size and shape, slightly lengthened either longitudinally or trans- 
versely, about twelve to each turn. Surface with moderately strong, slightly oblique transverse lines of growth, 
becoming coarser on the under side at the edge of the umbilicus. Diameter of very large specimen three inches 
eight lines, proportional width of last turn ;4, height of last turn ;%, diameter across the margin of the upper 
keel 5%, across the row of nodules on the under side %. 
From the great size, small number, and irregular nodular character of the tubercles on the under side, and 
want of connecting ridge between them, I think this species perfectly distinct from all the varieties of S. pugilis 
from which of course it obviously differs in the entire absence of tubercles on the upper side. 
Position and Locality——One very large imperfect specimen of this rare species is in the collection from 
the lower carboniferous limestone of Kendal. 
STRAPAROLLUS PENTANGULATUS (Sow. Sp.) 
Ref. and Syn. = Euomphalus pentangulatus Sow. Min. Con. t. 45. f. 1, 2. + Hwomphalus Bronni Portk. Geol. 
Rep. p. 417. 
Desc.—Discoid, depressed, of five or six gradually increasing whorls, those of the spire most usually sunk 
below the level of the body-whorl, but occasionally slightly raised above it; middle of the periphery very convex, 
from whence the surface slopes with little convexity to a prominent keel a little outside the middle of the upper 
surface on all the whorls, from whence the surface slopes with often a slight concavity (at an angle of about 110°) 
to the suture which is simple ; on the under side the surface slopes with slight convexity from the periphery to a 
very obtusely rounded keel nearly in the middle of the under side, from whence the surface extends into the um- 
bilicus, with considerable convexity ; umbilicus very wide, exposing the inner half of all the whorls ; mouth very 
_ slightly indented by the preceding whorl, giving an obscure pentangularity to the section ; inner lip very thin, or 
interrupted in the middle. Surface crossed with fine obtuse direct or slightly oblique lines of growth, sometimes 
decussated on the middle of the periphery by a few obtuse, obscure spiral strize. Diameter two inches, pro- 
portional width of last whorl ;;;, of penultimate whorl 7°, from suture to keel on upper surface of last whorl ;;, 
height of last whorl 4, width of umbilicus (measured from the inferior keel) =. 
The variety in which the spire is a little elevated above the body-whorl has received the name ZL. Bronni 
from Col. Portlock, but merges in the most imperceptible manner into the more ordinary variety in which the 
middle of the spire is depressed. In very young specimens the inner lip is continuous, although very much 
thinner than the other parts of the peritreme. There is no sinus in the lines of growth, although they are 
slightly thickened in passing over the upper keel. The transverse septa cutting off the old posterior whorls are 
very strongly marked in this species, leaving only one whorl and half to be tenanted by the animal. 
Position and Locality—Common in the lower carboniferous limestone of Derbyshire and Isle of Man; 
several internal casts probably of this species in the dark lower carboniferous limestone of Lowick, Northum- 
berland. 
STRAPAROLLUS PILEOPSIDEUS (Phill. Sp.) 
Ref. and Syn. = Euomphalus id. Phill. Geol. York. Vol. II. t. 13. f. 6. = . elausus Sow. Min. Con. t. 633. f.1. 
Desc.—Discoid, of about five gradually increasing, much embracing whorls ; spire truncated, all the whorls 
rising to the level of the sutural edge of the last one; suture canaliculate with a tumid margin, periphery very 
