258 EOCENE MOLLUSCA. 
Specimens occur, constituting a local variety, in which the ribs are more distant 
and prominent, and extend to the very front of the shell; four or five distant, elevated, 
concentric lines cross the whorl over the anterior canal, and are granulated at the 
points where they are intersected by the lengthened ribs; elsewhere the whorls 
are smocth. 
A miocene shell, described by Brocchi (Murex reticulatus—Pleur. ramosa, Bast.), 
presents a very close analogy with this Pleurotoma, as well in the general shape as in 
the character of the ornamentation ; it is distinguishable, however, by the greater size 
of the shell, which attains a length of nearly three inches, the greater narrowness 
and the simple margins of the whorls, the relatively longer spire and shorter aperture, 
the shape and position of the sinus, and the condition of the outer lip, which is 
smooth within. A Pleurotoma also occurs in the nummulitic beds near Pau, 
described by Rouault (Pleur. Tallavignesii), to which I have referred some shells from 
Nuneham and Southend, and which, in the young state particularly, much resembles 
the present species; but in that shell the whorls are more contracted in front; the 
posterior margins spirally lined, wider, and not so depressed; the longitudinal 
plications are more oblique, the lineation finer and more close; the anterior canal 
longer ; the outer lip more arched ; and the sinus not so deep. 
Size.—Axis, 10-12ths of an inch nearly; diameter, rather more than 3-12ths 
of an inch. 
Localities —Bramshaw, for the type; Brockenhurst, for the variety. 
No. 180. PievroroMa BrevirostruM. Sow. Tab. XXIX, fig. 6, a, 3. 
PLEUROTOMA BREVIROSTRUM. Sow. 1823. Min. Con., vol. iv, p. 120, t. 387, fig. 2. 
— — Bronn. 1848. Index Paleont., p. 1002. 
— — D’ Orb. 1852. Prodrome de Paléont., 25° Etaye, No. 411. 
Nec PLEUROTOMA BREVIROSTRUM. Sism. 1847. Syn. Meth. Anim. Invert. Pedem. foss., p. 32. 
nec _— — Bell. 1847. Pleurot. Foss, del Piem. (Mem. R. Accad. delle 
Se. di Torino), p. 607, t. 4, fig. 9. 
nec — — Naumann. 1853. Atlas zu sein. Lehrb. der Geogn., t. 70, 
fig. 4. 
P. testa elongata, angustd, turritd, longitudinaliter nodo-costata, concentrice lineata : 
spird elevatd, acuminata : anfractibus medio angulatis ; marginibus posticis latis, declivis, 
vie cavatis, sub-levibus, ad suturam incrassatis ; ultimo anfractu brevi, antice coarctato ; 
costis crassiusculis, brevibus; lineis concentricis filiformibus, sub-regularibus: apertura 
obovatd, in canali brevi, mediocriter lato, leviter arcuato et retrorsum refleco exeuntt ; 
sinu lato, profundo, subtrigono, media in margine collocato. 
Shell narrow, elongate, turreted, longitudinally ribbed, and spirally lined: the 
spire, which consists of nine volutions exclusive of the pullus, is pointed and much 
elevated, forming nearly two thirds of the entire shell. The whorls are sharply 
