TEREBRID^E. 223 



Sub-gen. am^a, H. and A. Adams. 



Shell turreted, thin ; whorls united, cancellated, with a few 

 thin, irregular varices ; aperture semilunar ; inner lip gibbose in 

 the middle ; outer lip thin, simple. 



magnifica, Soiv. Martinii, Wood. 



Genus cirsotrema, Morch. 



Shell turreted, solid; whorls cancellated, with a few 

 thick, irregular varices; aperture circular; outer lip with 

 a thick, crenate, marginal varix. 



Ea,\ C. vavicossi, Lamarck, \)\. 23, ^g. 9. Operculum, 

 C. varicosa, fig. 9, a, 9, h. 



The shells of this genus may be known from those of 

 Scala by the peculiar cancellated structure of the whorls, 

 and by the varices being fewer and non-continuous. 



Species of Cirsotrema. 



bicarinata, Sow. granulosa, Quoy and Gahn. 



cochlea, Sow. hyalina, So\v. 



crassilabrum, Sow. raricostata. Lam. 



crenata, Linn. suturalis, Hinds. 



decussata. Lain. unifasciata. Sow. 



diadema, Sow. varicosa, Lam. 



Fam. TEREBRID^. 



Teeth and lingual membrane rudimentary or none. 

 Tentacles very small or wanting; eyes on the tips of ten- 



