SO CLASS GASTEROPODA. 
M. de Lamarck separates from all the murices of Bru- 
guiéres, the 
RANELLA, Lam., 
Characterised by opposing varices, so that the shell is 
burdened with them on both sides; their canal is short, and 
their surface studded with mere tubercles; margins of the 
aperture folded. (Mur. Bufo, Mont., &c.) 
The APOLLES, Montf:, are merely umbilicated ranelle. 
(Murex gyrinus, List. 939. 34.) 
Fusus, Brug., 
Comprises all shells with a salient and straight canal, which 
are destitute of varices. 
When the spire projects, the columella is without folds, and 
the margin is entire, they are the FUSUS, properly so called, 
Lam., which Montfort again subdivides ; when they have no 
umbilicus, they are his Fusus. (Mur. cochlidium, Seb., &c.) 
The shortest and most swollen gradually approach the form 
of the buccina. (MM. tslandicus, Martini, &c.) 
When provided with an umbilicus, they are his LATHIRA. 
(Mur. Vespertilio, Martini.) 
The STRUTHIOLARIE are distinguished from the true fusi 
by a border which surrounds their aperture, and which covers 
the columella. ‘The margin of the adult is inflated, which 
connects them with the murex. (Mur. stramineus, Gmn., &c.) 
When the spire is salient, the columella without folds, and 
there is a small indentation or well-marked notch in the 
margin near the spire, they are the PLEUROTOMA, Lam. 
(Mur. babilonius, L., &c.) 
The CLAVATUL, in which the emargination is wide, and 
reaches to the spire, are also properly distinguished. 
When the spire is but slightly marked, flattened, or rounded, 
