NEPTUNKA DESPECTA. 161 



in specimens from the Crag generally three-fourths the total length; orna- 

 mented on the upper whorls by 2 or 3, and on the last by about 10 spiral ribs, 

 closer together towards the base of the shell; in the type form they are not very 

 prominent, having fine thread-like, wavy and irregular lines between them ; suture 

 distinct; s{)ire comparatively short, rapidly diminishing to a blunt and sub-mam- 

 miform point ; mouth large, ovate, together with the canal more than half the length 

 of the shell, angulate above; outer lip expanded, regularly curved, not distinctly 

 angulated by the carination of the body-whorl in the type as in some varieties ; 

 inner lip forming a glaze upon the pillar ; canal short, wide, open, turning to the 

 left, ending in a well-marked notch. 



Dimensions. — (Of Crag specimens). L. 80 mm. B. 50 mm , occasionally larger. 



Distribution. — Recent : Norwegian coast from Bergen to Finmark, Christiania 

 fiord, Lofoten Islands, Iceland, Spitzbergen, (Greenland. 



Fossil: Waltonian Crag: Walton-on-Naze (unique). Little Oakley, 

 not very common. Newbournian. Butleyan. Icenian. 



Pleistocene : Kelsey Hill, Holderness, Bridlington, Slains, Dalmuir. 



Denmark : Yo/r/m-clay. Southern Norway : Tnpes-h?inks. Western Sweden : 

 Uddevalla. 



Bemarlis. — The figures of this species given by Profs. G. 0. Sars and Brjzrgger 

 show the spiral costation as comparatively inconspicuous, but the former remarks 

 that in some specimens it is more prominent ; possibly such specimens may repre- 

 sent some of the varieties described below, which differ from the type in the cari- 

 nation of the whorls by the uppermost rib and the consequent angulation of the 

 outer lip. Scandinavian examples of N. despeda attain a larger size than do any 

 I have noticed in the Crag, that figured by Prof. Br^gger from the Pleistocene 

 deposits of Christiania measuring 135 mm. in length. One specimen from 

 Hollesley in my collection, however, measures 105 mm. by 65 mm. 



As before stated N. despeda and its varieties are the characteristic dextral 

 Neptuneas of the various zones of the Red Crag, N. antiqua being comparatively 

 rare in those deposits. 



Var. decemcostata, Say. Plate XVII, figs. 3, 4 ; Plate XXV, figs. 3, 5. 



1825. Fusus 10-costatus, Say, Jouru. Acad. Nat. Sci, Philad., vol. v, p. 214. 



1841-70. Fusus decemcostatus, Gould, Eep. Inv. Mass., ed. i, p. 287, fig. 202, 1841 ; ed. ii, p. 375, 



fig. 642, 1870. 

 1848. TropJwn antiquum, var. carinatum, S. V. Wood, Moii. Crag Moll., pt. i, p. 44, tab. v, fig. 1 b. 

 1882. Trophon antiqtius, var. despedus, S. V. Wood. Mon. Crag Moll, 3rd Suppl., p. 2, tab. i, fig. 9. 



Varietal Gharaders. — Corresponding with the typical Crag form of N. despeda 

 except that its spiral sculpture is much more prominent, consisting of strong and 



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