13G PLIOCENE MOLLUSCA. 



to it. At the British Museum (Natural History) it is called Latirm; at Jermyn 

 Street and the Sedgwick Museum (Cambridge), Trophon; and in Morch's collection 

 at Copenhagen, TJrosalpinx ; while Dr. Dall has figured somewhat similar forms 

 from Alaska as Tritoiiojusns {Plic'ifiisnii), though he has grouped with them some 

 shells nnder the latter name, which diifer materially from the Crag fossils in 

 question. 1 Tritonofusus, moreover, described as without, or with feeble axial 

 sculpture, the type taken for which is Ftisus i'^Iandiciis, has been associated by 

 him with Siplbonorhis, while he regards Fusus Kroi/e)i and F. spltzbergensis as 

 typical of Plicifusus, distinguished by feebler spiral ornamentation ; none of these 

 have any obvious connection with S. costifer. Latirus, Montfort (1810), originally 

 Latlti/rus, a genus allied to Fasciolnria, having two or three oblique folds on the 

 columella, and represented by L. ijibhidus, Gmelin, an Australian shell, seems 

 equally inapplicable. 



M. Cossmann refers our fossil to Chri/sodoiiius, and more doubtfully to 

 Buccinofusus^ the type forms of the latter given by him being the Recent 

 B. hernicieiisls, King, and B. par ills, Conrad, which is a Miocene species, but 

 neither of these has the strong longitudinal plication of S. costifer. I do not 

 think it should be referred either to Gkrijsodovius, Fmus, Trophon, or Urosalpinx, 

 wdiich latter belongs to the Muricidse ; our shell is not a Mnrex. 



These fossils form a fairly distinct group, specially characteristic of the Red 

 Crag, and common in the lower zones of it at Walton and Oakley. 



It is singular, however, that none of the shells described here under the generic 

 name of Senrlesia are known from the Belgian Crag. 



Almost unknown from European seas'* they occur in the Pliocene of Iceland and 

 in the Manx drift, while somewhat similar forms are living, according to Dr. Dall, 

 in Alaska. 



Under the circumstances, and to avoid further confusion, I suggest for the 

 Crag fossils and for some others which I venture to group with them the 

 generic name above given, in which I trust they may at last find a permanent 

 resting-place. 



Searlesia costifer (S. V. Wood). Plate XIII, fig. 1. 



1811. Murex rucjosus, Parkinson, Org. Rem., vol. iii, p. 64. tab. v, fig. 16. 



1812. Murex rugosus, J. Sowerby, Min. Conch., vol. i, p. 75, tab. xxxiv, fig. 1. 

 1835. Fusus costatus (rugosus), J. Sowerby, Syst. lud., p. 247. 



1848. Trophon costiferum, S. V. Wood, Mon. Crag Moll., pt. i, ]). 48, taf. vi, fig. 9. 



1 Eep. U.S. Nat. Mus., vol. xxiv (1902), p. 523. 



2 Ess. Pak'oconch. Comp., vol. iv (1901), pp. 35, 100. 



'■' The British species Fusus fenestratus = Buccinum fusiforine, Broderip, seems a nearly allied 

 form. 



