118 CRETACEOUS GASTROPODA 
made in these species. Several of them, as, for instance, Neptunea anomala, funicu- 
lata, fusoides and others (Adams. I, p. 80) must be referred to Tritonidea, and again 
species as Cantharus (Tritonidea) biliratus, nigricostatus, pastinaca and others (ibid, 
p. 85,) must be transferred to Hindsia of the Trrronmpa. 
Gray (Beechy’s Voy., p. 112) quotes Buccinum (Clavella) distortum as a Pollia, 
and it is indeed remarkable the similarity which young specimens of this species 
have with Pollia, so that it may be after all proved, that the Clavelle without a 
longer canal are only abnormally grown specimens of Pollia. If this could be 
proved the name Clavellithes must necessarily be avoided. 
As indicated, there must certainly be great alterations introduced, if the two 
genera Pollia and Tritonidea are to stand, but the numerous fossil species seem 
fully to indicate and to justify such a separation. Several species of both genera 
are described by Deshayes, Hérnes and others under Fusus and Murex (vide Foss. 
de Paris, Pl. 76 and Wiener Moll. Pl. 25, respectively). 
The cretaceous species belong chiefly to Tritonidea, and are more numerous 
than in any other genus of the ruszv2; they are in fact the predecessors of the 
Trironiw# or rather perhaps of the wvricrv#, and it is only questionable whether it 
would not be better to place them in the next sub-family. The form of the shell 
agrees better with the mwvricryv“, while the form of the aperture excludes them. 
Most of the /usus described by D’Orbigny belong to Tritonidea, thus forming a 
transitional group between /usus (as restricted) on the one, and Murex and 
Hindsia on the other side. Several other European cretaceous ruszv# have to be 
transferred to Pollia and Tritonidea, but scarcely any representatives of them are 
known from North America, at least none of the Neptunea or Fusus, lately described 
by Gabb, are so well marked as to be reasonably transferred to any of those genera. 
We shall describe from the South Indian cretaceous deposits four species under 
Tritonidea, namely, T. gibbosa, Stol., T. Requieniana, D’Orb., T. granulata, Stol., 
T. Trichinopolitensis, Forbes, sp. and one Pollia, b. Pondicherriensis, Forbes, sp. 
Pisania (Pusio) and Metula appear to be better classed with the Cozumsrtrrp» 
according to Gray. 
I have thus given a review of the genera of the rusry#, merely to shew what 
forms seem to be represented in the cretaceous formations, and how they may be 
traced. Were our fossil, mesozoic, materials usually better preserved, I have no 
doubt that several typical forms could be distinguished with generic names; and 
that in this way only can the daily doubts and objections as to species, which all are 
termed /usws, be cleared up. 
Pictet (Mat. Pal. Suisse, 3me. Ser. pt. II, pp. 642—650) enumerates 106 species of 
Fusus (= Fusiv® and FULGURIN# ) from the cretaceous deposits of Europe only. 
There is not the slightest question, that not much more than half of these are true 
species properly belonging to this (and the former) sub-family, but it is difficult 
to say, when, or whether we shall ever come to such a knowledge of them as is 
desirable. It cannot be wondered at, that nearly every one, having procured a good 
