OLIGOTOMA DECORATA. 217 



1872-9. Pleurotoma crls])ata, S. V. Wood, Mon. Crag Moll., 1st Suppl., pt. i, p. 35, pi. vi, fig. 13, 



1872 ; P. pannus, 2iid Suppl., p. 21, pi. iii, fig. 6, 1879. 

 1890. Oligotoma /estiva, E. Vincent, Bull. Soc. Roy. Malac. Belg., vol. xxv, p. 93, figs. 

 1892. Pleurotoma /estiva. Van den Broeck, Bull. Soc. Belg. Grcol., vol. vi (Memoires), pp. 121, 132. 

 1912. Pleurotoma /estiva, Tesch, Med. v. d. Rijks. v. Delfstoffen, pt. iv, p. 88, no. 221. 



Specific Ghavacters. — Shell elongate, subfusiform, tiirreted ; whorls 8, but little 

 convex, excavated above, slightly carinated, the last abont equal in length 

 to the spire ; covered with fine thread-like spiral ridges, the keel being ornamented 

 by short and oblique longitudinal plications ; suture slight ; mouth oval, narrow, 

 angulated above ; outer lip gently rounded, not expanded ; canal short, somewhat 

 twisted or turning towards the right ; columella with a prominent fold. 



Dimensions. — L. 18 mm. B. 6 mm. 



Distrihutvni. — Not known living. 



Fossil : Coralline Crag : Gedgrave, Boyton. Waltonian : Little 

 Oakley. 



Scaldisien : Belgium, Holland. 



Miocene : North Germany, Holland, Belgium, Vienna basin. 



Bemavlis. — I have given below (p. 226) my reasons for thinking that the shell 

 described by Wood {op. cit.) as Pleurotoma crispata does not accurately represent 

 the Italian fossil known as Drillia crispata, Jan, agreeing rather with the Miocene 

 species 0. festiva, and the same view has been taken by the Belgian and Dutch 

 authorities quoted above. I figure an example from Oakley, which seems to 

 correspond with that of Wood, together with some others from the Coralline Crag 

 and from Antwerp for comparison. 



Vincent identified the Scaldisien Pleurotoma granulina, Nyst,^ with 0. festiva. 

 I understand the type specimen of the former cannot be traced, but if it was 

 correctly drawn, I doubt whether these shells are the same. I have not 

 observed anything like Nyst's figure of P. (jranulina. in the East Anglian Crag. 



Oligotoma decorata (A. Bell, MS.), sp. nov. Plate XXVII, figs. 3, 4. 



Specific Characters. — Shell slender, sub-cylindrical ; spire elongate, regularly 

 diminishing in size, not much excavated below ; whorls but slightly convex, the 

 last about half the total length ; ornamented by spiral ridges with a double line of 

 tubercles just above the suture, and by oblique lines of growth, specially 

 conspicuous on the body- whorl ; suture shallow but clearly marked ; mouth long, 

 narrow, passing gradually into the canal without a distinct break ; outer lip 

 regularly curved, not expanded ; canal short ; columella sinuous, with a distinct 

 fold upon it. 



1 Conch. Terr. Tert. Belg., p. 43, pi. iii, fig. 7, 1881. 



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