OF SOUTHERN INDIA. 263 
characteristic species of the genus from the jurassic deposits of the Normandy. A 
large number of species described by D’Orbigny under the names of Turbo and 
Trochus belong to this genus. 
2. Hamus, Klein, 1753 (Tectarius, Valenc.; Pagodus, Gray). This name of 
Klein has full authority ; it is distinctly quoted in his list of genera and explana- 
tion of plates; the figure is a good one, (vide Tent. Meth. Ostr., p. 25, pl. 2, 
fig. 37). 
38. Hchinella, Swainson, 1840. 
4, ILittorina, Férussac, 1821. Probably the smooth species, with depressed 
spira, placed by Adams in the following sub-genus— 
4a. Neritoides, Brown, could be generically distinguished; they are nearly 
allied to Lithoglyphus. 
4b. Spironema, Meek, 1864 (Smith. Misc. Coll., No. 177, Check list cret. foss., 
pp. 19 and 35,) agrees in the thin structure of the shell with Amberleya, and gives 
the impression of being a not fully grown Littorina. Meek quotes two American 
cretaceous species, Sp. tenwilineata, Meek and Hayden, and Sp. bella, Conrad ; 
the first has originally been described as a Turbo, and the second as a doubtful 
species of Tuba; Jour. Acad., Nat. Sc., IV, p. 289, pl. 46, fig. 38. Both species 
are spirally striated, like Litéorima. 
4c. Oyclonema has been proposed by Hall (Paleeon. of New York, 1852, 
Vol. II, p. 89,) for a number of palzeozoic shells, which apparently do not differ in 
any essential characters from Jittorina, excepting that the shell is stated to be 
somewhat thinner. A few species, which we had occasion to examine, have, how- 
ever, hardly a thinner shell than many other species of Littorina. The surface is 
usually covered with fine spiral and transverse striz. ; 
5. <A few large, and generally reversed species, like Zurbo Bertheloti, d’Orb.- 
(Pal. frane. jur. II, p. 387, pl. 328, figs. 7-8), or Zurbo Hornesi, Stol. (Sitz. Akad., 
Wien, 1861, XLIII, p. 176, pl. 2, fig. 14), from liassic deposits, have most probably 
to be separated into a distinct genus, belonging to this sub-family. 
The same, or at least very similar forms, like Hehinella and Hamus, have been 
referred by Sandberger and other paleontologists to Littorina. There is a large 
number of palzeozoic, mostly smooth shells known under those names, exhibiting 
close relationship to the Zzrrorzvipz# in general, and most of them belong very 
probably to this family, though in some respects they resemble the Cazuyrrzup% 
or Narrcrpm. It will be sufficient here to refer to genera, like Platyostoma, Conrad, 
Holopea, Hall, Macrocheilus, Phillips, &c. Generally speaking, the Lrrrormip# 
are represented among the oldest known Gastropoda, and they are found more or 
less in all sedimentary deposits. 
It is difficult to understand for what reason D’Orbigny refused to acknowledge 
any cretaceous Littorine, and referred species, which were described under that name, 
to Turbo, Trochus, and other genera. This celebrated author’s opinion, having been 
subsequently accepted by many paleeontologists, has rather retarded the true know- 
ledge of the fossil Lrrrorivipz. Even Pictet, in his last review of the cretaceous 
species of ZirrorinipZ (Mat. Pal. Suisse. 3me. Ser., Foss. Ste. Croix., p. 365), is not 
