128 CRETACEOUS GASTROPODA 
Localities. —Alundanapooram, neighbourhood of Anapaudy and Verazhoor, in 
the Trichinopoly district ; a tolerably common shell. 
Formation.—Trichinopoly group. 
ce. Sub-family,—MURICIN#. (Adams, Chenu, Gray and others.) 
The animals of the wvrrcrv# are almost exactly like those of the rvsry#, at least 
they do not exhibit any greater variations, except that the margins of the mantle are 
generally more developed and form usually at an interval of one-third of each 
yvolution stronger spinose or lamellar varices in the former sub-family. The aper- 
ture of the shell is round, internally smooth and only the margin of the outer lip 
often undulated; in a great number of species the canal is externally, up to a 
narrow open line, closed; the operculum is ovate with a sub-apical nucleus. 
It is certainly necessary to divide this family into at least four genera (or rather 
five) as proposed by Dr. Gray (Guide, 1857, p. 11) and others. 
1. Murex, Linn. 1758, restricted to the species with a short spire, ventricose, 
strongly convex whorls, thick varices with or without single spines, and along canal. 
The W. spirilla=? Tudicla of Adams and Chenu excluded. 
2. Chicoreus, Montfort, 1810, with three principal and more or less sub-equal 
spinose and lamellarly branching varices, last whorl usually somewhat higher than 
the spire, canal short with its termination bent to the right. 
2a. Pteronotus, Swains. 1840.—Of the other sub-genera, quoted by Adams, 
this ought I believe to be established as a genus, comprising chiefly elongated shells 
with the spire about the same height as the last whorl or even somewhat higher, 
each whorl ornamented with three laterally much compressed, fin-shaped varices ; 
secondary varices more or less obsolete, the interspaces being often quite smooth, 
the canal of moderate length, externally usually perfectly closed by the extended 
margins of the aperture, the termination straight or only very slightly bent. 
There are a considerable number of tertiary fossil species, which indicate this 
separation as very desirable. 
3. Typhis, Montf. 1810, characterized especially by the tubular canal near the 
posterior edge of the mantle; includes a large number of typical shells. 
4. Trophon, Montf. 1810.—The varices are numerous, lamellar, single and 
equally formed, posteriorly angulated, prolonged into short lamelliform spines, hol- 
lowed out internally; the anterior canal is open, of moderate length and usually 
bent to the left (in the frontal view of the shell). 
The sub-family, as at present restricted, forms a very well defined, natural 
group of shells, and each of the genera, as here stated, have numerous representa- 
tives in neogene and eocene beds. By much less certain, however, is any know- 
ledge of the cretaceous species, attributed to this same group of shells. The fol- 
lowing cretaceous species have been recorded by Pictet (Pal. Suisse, 3me 
Ser. p. II, p. 660); I. Prestensis, P. et Camp; HW. Genevensis P. et R.; 2. carinella, 
