SYSTEMATIC 173 



Pleurotomella? anomalapex n.sp., PI. VI, fig. 19 



Shell small, white, fusiform with strongly convex and weakly shouldered whorls, sculptured with 

 dense, wavy, spiral lirations and protractively arcuately oblique axials. Whorls five, including a blunt 

 paucispiral, smooth protoconch of two whorls. Spire-whorls sculptured with ten to twelve spirals, 

 body-whorl including base and neck with about forty-spirals, shoulder without spirals. Axial sculpture 

 of narrowly rounded, oblique axials, which commence strongly at the shoulder, but become subobsolete 

 over the lower half of the whorls. There is a weak surface pattern also, of dense axial threads which are 

 more apparent on the otherwise smooth concave shoulder. The posterior sinus is deep, Daphnellid 

 reversed L-shaped, and the outer lip swings forward in an arcuate sweep. The anterior canal is sharp and 

 comparatively straight, its length emphasized by the relatively long neck, resulting from an excavated 

 base. 



Height 7-8 mm. ; diameter 3-9 mm. 



Type locality. St. WS 225. Between Falkland Is. and Patagonia, 50 20' S, 62° 30' W, 9 June 1928, 

 162-161 m. (holotype only). 



The species resembles ohlini, but has the addition of well-developed axials. Although both these 

 species lack the sinusigerid protoconch of the genotype, the adult characters of build and sinus are in 

 accord with Pleurotomella. I have already referred to Dall's view that some Turrids commence with 

 a horny sinusigerid envelope which wears off and leaves a limy mould in its place. The somewhat 

 irregular shape and minute surface malleations of the nucleus in two of the above species, and especially 

 the raised terminal varix, seem to be in accord with Dall's explanation. 



Genus Eumetadrillia Woodring, 1928 

 Type (o.d.) : Agladrillia {Eumetadrillia) serra Woodring Miocene, Jamaica 



The shells which I have referred below to Smith's unfigured fuegiensis seem to represent the adult of 

 that species. They certainly tally with Smith's description better than they do with any other Magellanic 

 ' Drillia' known to me, and most of them have been adequately figured by Strebel (1905, 1908). 



The shells before me match Smith's description in every particular — protoconch, number and 

 very oblique trend of the axials, which are thickest above, smooth concave shoulder, aperture two- fifths 

 the total height, sinus deep, and even the purplish pink colour. Also, young examples approximate to 

 the dimensions cited by Smith. 



The generic location seems to fall between the Recent and Tertiary Austro-Neozelanic Splendrillia 

 Hedley, 1922, and Woodring's Eumetadrillia, with more leaning towards the latter. 



The protoconch is large, broad and dome-shaped as in Splendrillia, but the shoulder is entirely free 

 from the subsutural spiral fold which is so characteristic of that genus. Although the protoconch in 

 Eumetadrillia is rather slender the smooth concave shoulder and general features of build and axial 

 ribbing are in accord with those features in the Magellanic shell. 



Most of the ' Discovery ' shells have a very weak parietal callus, but in one aged example this feature 

 is quite as well developed as in Woodring's genotype. 



Eumetadrillia fuegiensis (Smith) 



Pleurotoma (Surcula) fuegiensis Smith, 1888, p. 300. 



Type locality. Strait of Magellan. 



St. WS 85. 8 miles S 66° E of Lively I., East Falkland Is., 52° 09' S, 58° 14' W to 52° 08' S, 58° 09' W 



25 Mar. 1927, 79 m. 

 St. WS 88. Off north of Staten I., 54° S, 64° 57' 30" W, 6 Apr. 1927, 118 m. 



