Lamarck's Genera of Shells. 255 



Type. Phasianella bulimoides*. (Buccinura australe. 



Gmel.) 



Shell oblong-conical, rather thin, smooth, palish yellow, 

 transversely fasciated ; fasciae numerous, variously variegated 

 and spotted ; apex of the spire acute. New Holland. PI. VIII. 

 Fig. 170. 10 Species. 



8. Turritellat.. 



Shell turrited, not pearly. Aperture rounded, entire, margins 

 disunited at the upper part, not reflected outwards ; a sinus in 

 the right lip. Operculum orbicular, horny. 



Distinguished from turbo by the general form of the shell, 

 and by the sinus on the right lip, a constant character. Most 

 of the species are transversely carinated or striated, but none 

 of them have vertical ribs, varices, or tubercles. 



Formerly all the turrited shells were called screw shells. 

 Thus turritella, scalaria, cerithium, ^-c, were all confounded 

 with the true screw shell, terebra. 



Type. Turritella duplicataX. (Turbo duplicatus. Linn.) 



Shell turrited, thick, heavy, transversely sulcated and ca- 

 rinated, whitish yellow, apex reddish ; whorls convex, cari- 

 nated; the two middle carinse most prominent. Coast ofCoro- 

 mandel. PI. VIII. Fig. 171. 13 recent Species, and 2 fossil §. 



Section II. 

 Trachelipoda with a projecting siphon. (Zoophaga||.) 

 The animals of this section breathe only water, which is 



conveyed to the branchiae by the projecting siphon. They are 



all carnivorous, marine, without jaws ; and have a retractile 



proboscis. Two tentacula on the head. 



Shell spirivalve, ensheathing, aperture canaliculated or 



notched, or merely inclined at the base. 



• Resembling a bulinms. + Dim. from tmris, a little tower. 



I Doubled, because it is bi- carinated. 



$ Desniarets has described a new genus, established by Freminville 

 which we sliall add in this place. It has been called Rissoa ; we give a 

 figure of one species. 



Shell univjilve, oblong or turrited, generally furnished with prominent 

 longitudinal ribs, aperture entire, oval, oblique ; no canal at the base ; no 

 tooth, nor plait ; margins united, or nearly united ; right margin inflated, not 

 reflected. No umbilicus. Gulf of Genoa. Fig. 172. {Vide Nouveau Bul- 

 letin des Sciences, or Nouveati Dictionnaire d'Histoire Naturellc.) 



II Cnmivorus. 



Vol. XV. S 



