MitrginfU't.] 



GASTROPODA. 



457 



Several hundred Recent species have been described. They live 

 on sandy and rocky coasts of warm and tropical seas. Found in 

 depths to 390 fathoms. 



Fossil in the Tertiary from the Eocene. 



KEY TO SIJBGENEKA. 



A. Shell oval, usually with a basal sinus ; spire moderately ele- 



vated ; the varix of the outer lip not ascending on the 



spire . . . . . . . . . . . . MARGINELLA. 



B. Shell cylindrical ; the outer lip usually contracted and without 



a varix ; spire very short . . . . . . . . VOLVARINA. 



C. Shell with a prominent spire, the base not emarginate ; the varix 



of the outer lip ascending more or less on the spire ; the 



lowest two plaits usually close together . . . . GLABELLA. 



Subgen. 1. MARGINELLA, s. str. 

 Sect. 1. MARGINELLA, s.s. 



Shell ovoid or ovato-conic, somewhat ventricose above ; the spire 

 usually short, not exceeding in height that of the aperture ; proto- 

 conch paucispiral, the nucleus depressed ; the whole surface covered 

 with enamel ; the suture linear, indistinct ; the body-whorl narrowed 

 towards the base ; aperture high and narrow, somewhat channelled 

 above, truncated and mostly lightly emarginate at the base ; outer 

 lip thick, with an outer varix, lightly retrocurrent toward the suture, 

 smooth inside ; columella oblique, nearly straight, with 4 rather distant 

 and slender plaits, the uppermost almost transverse, the lowest nearly 

 vertical and extending to the basal margin ; inner lip very thin, not 

 easily distinguished from the enamel which covers the shell. 



KEY TO SPECIES. 



A. Outer lip smooth inside. 



. Height of .spire a little less than that of the aperture ; apex 



obtuse . . . . . . . . . . . . fusula. 



aa. Height of spire a little less than half that of the aperture ; 



apex sharp . . . . . . . . . . Stewartiana. 



B. Outer lip with a few tubercles inside ; shell biconic , height of 



spire a little less than that of the aperture . . . . All port i. 



1. Marginalia fusula, Murdoch and Suter, 1906. Plate 20, fig. 9. 



Marginella fusula, M. & S., T.N.Z.I., xxxviii, 1905 (190(i), 289. pi. 23, 

 f. 23, 24. 



Shell small, rather thin, oval-conic, smooth and glossy, and with a 

 much produced spire. Sculpture consisting of low rounded growth- 

 periods, numerous and irregular, usually more marked on the last 

 ha If -volution. Colour white or with a faint yellow tinge ; occasionally 

 some indistinct brown markings which form 2 spots on the outer lip, 

 and seem to indicate the presence of 2 brown spiral bands on the 

 body- whorl in fresh specimens. Spire produced, a little shorter than 

 the aperture, conical, with an obtuse rounded apex. Protoconch 

 paucispiral, smooth, rounded, nucleus depressed. Whorls 4, flatly 



