OF SOUTHERN INDIA. 405 
bands; columella rather thin, twisted, hollowed out. The recent species are also 
peculiar to the eastern seas, they live on coral reefs or sea-weeds. Of fossil species 
the jurassic Bulla undulata, Bean, B. Loliolwm, Morr. et Lycett (Moll. Great Ool., 
p- 96, pl. 8, figs. 8 and 16), or the Bulla pulchella, Desh. (Paris foss., 2me. ed., pl. 40, 
figs. 19-21) and others may belong to this genus. Perhaps some of the species 
of Globiconcha, which are only known from casts, may also he referrible to 
Hy datina. 
“15a. Bullopsis, Con., 1858 (Jour. Acad. Philad., 2 ser., III, p. 334, and IV, 
pl. 46, fig. 27), has the general form of Hydatina with a depressed spire and 
inflated last volution, but the inner lip has two close folds. The genus has been 
proposed for a cretaceous species from Mississippi, Bull. cretacea. 
ce. Sub-family,—RINGICULIN 2. 
This sub-family was first proposed by Meek in the American Journal, 
vol. XXXV, p. 87. The shells in general resemble Act@on, except that they 
have the margins of the aperture strongly thickened and externally varicose, the 
columella is twisted or plaited, and always terminates anteriorly with a distinct 
fold, in front of which there is a groove or a kind of canal in the thickened margin, 
not, however, extending to the structure of the shell itself so as to be traceable by 
the strize of growth. 
The animal of Ringicula, the only recent genus belonging to this sub-family, 
resembles, according to Woodward, that of Act@on, but the teeth are like those of 
Philine, being only two in each series, large, converging, and curved almost in a 
semicircle; there are often one or two smaller outer laterals, the central ones are 
wanting ; an operculum is not known. 
Meek (Check list cret. foss. N. America, 1864, p. 34) says that from the 
examination of a drawing of a recent Ringicula, it appears that the animal has 
“a large well developed siphon, which lies (perhaps when the creature moves) folded 
back upon the body-whorl between two short unequal tentacular lobes.” Meek 
concludes from this the priority of constituting a distinct family Rrvercvzim=zZ for 
these shells, a selection which, if the observation of the animal proves to be a 
correct one, as seems very probable, would appear quite appropriate. We retain 
here provisionally the group as a sub-family simply to be able to classify the fossil 
shells easier, than could be done otherwise. 
The species belonging to the zzezcuzz first appear, so far as known, in the 
cretaceous period, being, however, here more numerous than at any subsequent time. 
The recent representative is Ringicula, with which I have compared well preserved 
specimens of all the other known generic types, and I must say that as far as struc- 
ture and form of the shell, especially that of the margins of the aperture, are con- 
cerned, there is great difficulty in considering these shells as more than sub-generic 
forms of Ringicula. Their principal characteristics are the thickened margins and 
the anterior termination of the columella with a fold, in front of which there 
5G 
