34 
to show the characters afforded by the teeth; some new ones, ren- 
dered necessary by the examination of the teeth of some genera, 
which had not before been described, are added. 
Suborder I. PRoBOSCIDIFERA. 
A. Hamiglossa. Teeth on lingual membrane in three series (1*1*1), 
the central broad, the lateral versatile (figs. 1-4). 
Fam. 1. Muricip#. Head truncated ; tentacula moderate; lateral 
teeth flat, with a bent-up process at the end more or less at. right 
angles with the base ; siphon of mantle and canal of shell straight ; 
foot simple in front; mantle enclosed ; pillar lip smooth (fig. 1). 
Fig. 1.—Chrysodomus antiquus. 
a. Muricina. Operculum ovate ; nucleus subapical within the apex ; 
varices of shell developed. Murex, Trophon. 
b. Fusina. Operculum ovate, acute; nucleus apical; varices of 
shell rudimentary or none. Pisania, Colus, ° Latirus, Chrysodomus, 
Clavella (Cyrtulus). 
°c. Pusionellina. Operculum semiovate ; nucleus in middle of the 
straight inner edge. Teeth 2 Pusionella. 
d. Rapananina. Operculum ovate, blunt ; nucleus elongate, form- 
ing the outer or hinder edge. Rapana, Rhinochilus, Chorus, Cuma. 
Fam. 2. Buccinip#. Head truncated; tentacula moderate ; 
lateral teeth flat, with a bent-up process at the end more or less at 
right angles with the base ; siphon of mantle and canal of shell re- 
curved ; foot simple; mantle enclosed ; pillar lip smooth. 
a. Buccinina. Operculum ovate ; nucleus small, near outer front 
edge. Buccinum, Pseudoliva. 
b. Nassina. Operculum ovate, acute, nucleus apical. 
* Operculum entire. Latrunculus, Cominella, Phos, ? Cyllene, 
Columbella. : 
** Operculum serrated. Bullia, Nassa, Desmoulia, ? Mingeria, 
? Northia. 
Ringicula probably belongs to Auriculade, as it is said to have the 
teeth of that family. 
c. Purpurina. Operculum oblong, nucleus elongate, forming the 
long outer edge. Purpura, Concholepas, Sistrum, ? Magillus. 
It is to be observed that the operculum of these two families offers 
exactly the same modifications. 
Planaxina, which have been arranged in this family, have a distinct 
rostrum and operculum like Littorina. 
