PROSOBRANCHIATA. 215 



raised lines, which, in well-preserved specimens, are decussated by the lines of growth ; 

 the middle part of the whorl in the adult shell is quite smooth, and the body-whorl, 

 which is rather longer than the spire, terminates in a long, narrow, nearly straight 

 canal, ornamented with numerous, somewhat irregular, obliquely transverse, raised 

 lines ; these lines, which are very fine and undulating, gradually become more and more 

 feeble as they ascend the canal, and ultimately disappear towards the middle of the 

 whorl. The aperture is ovately oblong ; the right lip very thin, and much arched ; 

 the sinus, which is placed in the margin, just behind the shoulder, is wide and 

 moderately deep. 



In the specimens from Lyndhurst (var. cypha), the whorls are more convex, the 

 posterior margins more depressed, and the outer lip less roundly arched than in the 

 typical form, and the shells themselves are smaller ; but in the ornamentation, and in 

 the position and shape of the labial sinus, they agree with P. transversaria, of which 

 they appear to be merely local varieties. 



The shells from Dax and the environs of Bordeaux, described by Grateloup, and 

 to which M. Deshayes refers as being possibly a variety of the Paris basin species, 

 are specifically distinct, and have been named P. opis by M. D'Orbigny; and the 

 specimen from Bracklesham Bay which Mr. Sowerby (Dixon's ' Geol./ &c.) has 

 referred to the present species, also appears to be specifically distinct, and I have 

 separated it accordingly under the name P. gonicsa. 



Our English specimens have attained a less size, and are somewhat narrower, 

 than the French ones, but in all other respects they agree well. 



Size. — Axis, 1 inch and 10-12ths; diameter, rather more than 7-12ths of an inch. 



Localities. — Brockenhurst, Lyndhurst. French — Parnes, Grignon, Chauraont (fide 

 D' Orb.) ; Marquemont, Lattainville, Hermes, Neuvillebose, Saint-Felix (fide Graves) ; 

 Betz, department de POise (fide Be Plain.) 



No. 142. Pleurotoma cymma, F. E. Edwards. Tab. XXVI, fig. 4 a, b. Tab. XXVII, 



fig. 9. 



P. testa elongato-fusiformi, latiuscidd, tuberculatd, undique spiraliter lineatd ; spird 

 elevatd, sub-conicd ; anfractibus convexis, angulatis ; marginibus posticis lalis, vix cavatis . 

 tuberculis numerosis, parvis, nodiformibus, obliquis ; lineis spiralibus confertis, siibtilissimis, 

 undulosis, antice eminentioribus, postice fere obsoletis : aperturd oblongo-ovali, in canali 

 longo, recto, exeunti ; labro arcuato, tenui ; sinu prof undo, in margine collocato. 



Var. nana. Testa minori, angustiori : canali longiori ? 



Shell rather broad, fusiform, with an elevated, nearly conical spire, formed of nine 

 or ten volutions: whorls convex, sharply angulated at the shoulders, where they present 



