PROSOBRANCHIATA. 213 
natd: anfractibus numerosis, angulatis, convexis, sub-ventricosis, in juventd tuberculatis ; 
marginibus posticis latiusculis, concavis ; ultimo anfractu in canali longo, recto, terminanti ; 
striis spiralibus numerosis, inequalibus, lineis incrementi asperatis ; striis duobus vel tribus 
ad humeros prominentioribus: aperturd pyriformi ; labro arcuato ; sinu lato, profundo, in 
margine collocato. 
Shell elongate, fusiform; spire much produced, pointed: whorls many (10—12), 
convex, somewhat ventricose, angulated at the shoulders, much attenuated, and pro- 
duced in front, the last whorl terminating in a long, straight, moderately wide canal ; 
the posterior margins are rather wide, depressed, channeled along the middle, and 
somewhat thickened at the edge, so as to present a broadish, slightly elevated border 
round the suture. The angulated shoulders, and depressed posterior margins of the 
whorls, give a turreted character to the spire. Two sharp, elevated, and rather distant 
spiral lines run round the border, and several faint and unequal lines traverse the 
hollow part of the margins. On the middle and front parts of the whorls the spiral 
lines are numerous, irregular, and unequal, a slender, thread-like line occasionally 
occurring between thicker and more elevated lines; two or three on the shoulder are 
more prominent and distant than the rest. The aperture is pear-shaped, rounded 
behind, contracted in front; the outer lip much arched; the sinus wide, very deep, 
sub-trigonal in form, and placed a little in front of the middle part of the margin. 
This elegant Pleurotoma is apparently confined to the middle eocene strata; it has 
hitherto been obtained only from Bramshaw and the synchronous beds at Bracklesham 
Bay. 
Size.—Axis, 2 inches and 9-12ths; diameter, 10-12ths of an inch. 
No. 140. PLEURoToMA GonrzaA, F. 2. Edwards. Tab. XXV, fig. 10. 
PLEUROTOMA TRANSVERSARIA, Sow. (non Lam.) 1850. Dixon’s Geol., &c., of Suss., p. 102. 
— Morris. 1854. Cat. Brit. Foss., 2d edit., p. 270. 
P. testd elongato-fusiformi, turritd, lineis spiralibus omnino tectd ; spird elevatd : 
anfractibus depresso-convexis, angulatis, obscure carinatis ; marginibus posticis latis, sub- 
concavis, ad suturam crenulatis ; ultimo anfractu in canali mediocri, subrecto, exeunti ; lineis 
spiralibus tenuibus, confertis, irreguluribus: apertura lanceolaté ; labro rotundo-arcuato ; 
sinu mediocriter lato, profundo, in margine collocato. 
Shell elongated, fusiform, turreted; spire elevated, apparently much exceeding 
the last whorl in length: whorls rather convex, flattened at the sides, and angulated 
at the shoulders, which slightly project, and present the appearance of an obscure, 
rounded keel; the posterior margins are very wide, hollowed out, and crenu- 
lated round the suture; the last whorl contracts rather suddenly in front, and 
28 
