128 riJOCENE MOLLUSCA. 



variety lamellosa {Fnsns lameUoHim, Gray), wliich is more slender, the body-wliorl 

 is not so tumid, and the longitudinal ribs are more numerous (fig. 7 c). Some 

 shells I found years ago in the March gravels, which occur elsewhere also in the 

 Pleistocene deposits, as at Kelsey Hill and the Clyde beds, referred to and figured 

 as T. Bamjjias by Wood, in his 1st Supplement (p. 26, tab. iii, fig. 11), are much 

 smaller and have about twenty ribs. They seem intermediate between T. clathratus 

 and T. trnncatns, but most nearly approach the latter. The type form of the Crag 

 corresponds with specimens in my collection from Uddevalla and the Pleistocene 

 beds of Christiania, except that the latter are larger and the ribs more numerous. 

 Prof. Br/srgger figures a specimen from the latter, 40 mm. long, as var. major. 

 The American form is still larger, the example figured by Gould measuring 45 mm. 

 by 20 mm. MM. Dautzenberg and Fischer describe the latter as TropJion chithratiis, 

 var. scalar if ormis. Except for its size it corresponds with the Crag shell. Prof. 

 Kendall and Mr. Lamplugh record both the type-form of the present species (here 

 figured, PI. XII, fig. 25) and T. Bamfjins from the Manx drift. 



Trophon Gunneri (Loven). Plate XII, fig. 26. 



1846. Tritonium Gunneri, Loveu, Ind. Moll. Scand., p. 12. 



1867. Trophon truncatus, var. scalaris, Jeffreys, Brit. Couch., vol. iv, p. 320. 



1872. Trophon Gunneri, S. V. Wood, Mou. Crag Moll., 1st Suppl., p. 27, tab. iii, fig. 18. 



1878. Trophon clathratum, var. Gunneri, G. 0. Sars, Moll. Eeg. Arct. Norv., p. 247, pi. xv, fig. 11. 



1887. Trophon clathratum, var. Gunneri, Kobelt, Icon. schaL'ntrag. europ. Meerescouch., vol. i, 



p. 25, pi. vi, fig. 9. 

 1903. Trophon clathratus, var. Gunneri, Lamplugh, Mem. Geol, Surv., Isle of Man, p. 475 

 1912. Trophon (Boreotrophon) Gunneri, Dautzenberg et Fischer, Camp. Scient. Pr. Monaco, vol. 



xxxvii (Mollusques), p. 151. 



Specific Characters. — Differs from T. clathratus in that the whorls are squarish 

 above instead of rounded, with a flat shelf below the suture ; the longitudinal 

 lamellar ribs are more prominent, with a thin knife-edge and angulate, having a 

 spine-like point at the angle. 



Dimensions. — (Of the Crag shells.) L. 20 mm. B. 10 mm. 



Distribution. — Recent: Shetland (Jeffreys). Norwegian coast, Spitzbergen, 

 New England (D. & F.). 



Fossil : Icenian Crag : Bramerton, Thorpe, near Norwich. 



Pleistocene: Scotland jijassMw, Belfast, Isle of Man, Bridlington,' {Kelsey Hill, 

 March gravels. 



BemarJcs. — This form, which was originally described by Loven as a distinct 

 species and recognised as such by M. Sars, Morch, Wood, and others, has been 

 more generally regarded of late years as a variety of T. clathratus. MM. Dautzen- 

 berg and Fischer, however, state in their recent work, on the authority of 



