262 EOCENE MOLLUSCA. 
Nec Pinvrotoma uNDATA. Bast. 1825. Mem. Géol. sur les Env. de Bordeaux, p. 64, No. 7. 
nec _— — V. Hauer. 1837. Fossth. imtert. Becken vy. Wien. Jahrb., p. 419, 
No. 98. 
nec — — Grat. 1838. Cat. Zool., &c., du Bass de la Gironde, p. 46, No. 394. 
nec _— — Grat. 1840. Conchyl. foss., &c., du Bass. de l’Adour (Atlas 
Pleurot., t. 2, fig. 36). 
P. testa elongato-fusiformi, sub-turritd, lineis spiralibus costulisque longitudinalibus 
ornatd: spird acuminatd: anfractibus convexiusculis, postice sub-canaliculatis ; lineis 
concentricis crassiusculis, depressis, numerosis, undatis ; costulis undatis, variis: apertura 
angusto-ovatd, antice in canali brevi exeunti; labro tenuissimo, arcuato ; sinu latiusculo, 
marginibus sub-parallelis, anticd in margine collocato. 
Shell oblong, fusiform, somewhat turreted, ornamented with spiral lines and 
longitudinal ribs; the spire pointed, produced, always exceeding the last whorl in 
length ; whorls eight or nine (exclusive of a smooth, conical pullus of three volutions), 
convex, short, and bluntly angular on the shoulders. The posterior margins are 
slightly channelled; the sutural edges, in the young shells, are frequently bordered by a 
single row of small, roundish tubercles, which disappear on the fourth or fifth whorl, 
and the edges then become feebly and distantly crenulated, or they present three or 
four prominent, thread-like lines. The concentric lines are numerous, irregular, fine 
and thread-like over the margins, rather thick and depressed over the middle and 
front parts of the whorl, and slightly wavy on the last whorl; the longitudinal ribs 
are short, oblique, curved, and very variable in different specimens, both in size and 
number, sometimes being moderately large and distant, sometimes small and crowded. 
The aperture is of an oblong-oval form, and terminates in front in a short, somewhat 
narrow, and nearly straight canal; the outer lip is very thin, much arched, and 
expanded towards the middle; the sinus is moderately wide, deep, with nearly parallel 
margins, and placed in the very front of the margin, immediately behind the shoulder. 
The transverse lineation in the English specimens is, as is not unfrequently the 
case, of a coarser character than that found in the French shells; and there is also a 
slight difference in the condition of the posterior margins. These variations, however, 
do not appear to be of sufficient importance to justify the separation of the English 
shells. 
Size.—Axis, | inch and 2-12ths (30 millim.); diameter, nearly 5-12ths of an inch 
(10 millim.). 
Localities—Stubbington ; French: Grignon, Parnes, Mouchy, Courtagnon (fide 
Desh.), Saint-Felix, Ully-Saint-Georges (fide Graves), la Vallée de l’Aisne (fide 
Melleville). 
