OF SOUTHERN INDIA. 77 
b, Sub-family,—V OLUTIN A. 
We accept this sub-family in the same sense as Adams’ Vozrvrrpm, Gray’s 
voturin# or Chenu’s Voluta with a large number of sub-genera; and as all the 
principal forms are amply illustrated and noticed in Chenu’s Manual, it will be suffi- 
cient to refer to that publication. 
Chenu enumerates sixteen sub-genera, the greater part of which, we think, 
ought with full reason to be admitted as equivalent to generic distinctions; it will 
even be necessary to increase this number, when all the known fossil species shall 
have been properly attended to. Further sub-divisions of the whole group, as those 
of re7Tiv2, etc. Gray, or cyueiva and zzponin%, Adams, may be convenient, but the 
characters upon which they are based seem to depend very much on local modifi- 
cations of one and the same shell (as in Cymb. proboscidale, or in Melo ethiopica) 
and must, therefore, always be of subordinate importance. The known fossil species 
do not give much support to these minor sub-divisions, although I haye no hesitation 
in saying, they may be found both convenient and useful. 
The animals of the rozurrm are all remarkably similar in form; they have a 
large head with short stout tentacles, distant at their basis and united by a broad 
veil forming a hood over the head; the eyes are usually on thickened bulgings 
behind the base of the tentacles; the siphon is of moderate length, usually re-curved, 
and with more or less developed auricles on each side of the base, sometimes par- 
tially connected with the veil. The mantle is enlarged all round, as in Cymbium, 
Melo and others, covering the greater portion of the outer shell-surface with 
enamel, similarly to what has been already noticed in the mwareiverzivz; but it 
does not seem to have any filamentous appendices on the exterior surface, as in the 
Crprzip#. Sometimes it is expanded only on one, the columellar side, as in 
Volutella, D’Orb. The foot is generally of a simple triangular shape, adapted for 
creeping, truncate in front and prolonged posteriorly, as in the greater number of the 
remaining sub-families. 
The teeth are on a lingual membrane in one series only. A horny operculum 
has been observed by Gray in the genus Voluta, as restricted to species like V. musica, 
and lately by Crosse in several species of Lyria. (Vide Journal de Conchyliol. 1866, 
3 ser., Vol. VI, p. 105.) - 
The variety in form of the shells is very great, but they are so gradually con- 
nected with each other, that very great difficulty is experienced even in separating 
the known living species into the genera, as given in Chenu. A marked character 
of the shell of all vozurryz is the relatively great size of the last volution, the 
manillate apex, and the anterior plaits of the columellar lip being stronger than 
the posterior. Only where these characters have been observed, does there seem to 
be full reason for referring the fossil species to this sub-family. Of the cretaceous 
species many belong to Volutilithes and Lyria (the same is the case with the 
lower tertiary species): these two genera are, however, exactly those which form 
a gradual passage to the Fuscrozarip# and the urrriv# respectively. When insome 
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