OF SOUTHERN INDIA. diva. 
yet observed. The remains of stronger varices at shorter or longer distances would, on the other 
hand, rather speak against a Zerebra, and would be more in favor of a species of the Cerrruzp2. 
We have nothing to add from the South Indian cretaceous deposits. 
A few jurassic species have been described as Zerebra, namely, 7. melanoides, Phillips (Yorkshire, 
1829, p. 102, Pl. IV, Fig. 13), 7. granulata, Phill. (ibid. Pl. VII, Fig. 16), and the 7. Portlandica, 
Sow. (Trans. Geol. Soe. Lond. IV, p. 849, Pl. XXIII, Fig. 6). None of these is certain; the first 
was referred by D’Orbigny to Chemnitzia; the second by Lycett (Supp. Monog. of Moll. ete. 
1863, p. 10, Pl. XXXI, Fig. 12) on account of a single columellar fold (this would not prevent 
its being a Terebra) to Nerinea, and the third by D’Orbigny to Cerithium. 
XVIII. Family—PYRAMIDELLID A. 
Under this name we retain most of the typical forms of Pyramidella, Obeliscus 
and others, as stated by H. and A. Adams, and add to these the numerous fossil 
species known commonly under the name of Nerinea. 
The characteristics of the family may be put thus :— 
Turreted or broadly conical shells, with usually sinistral apex and the aperture 
anteriorly effuse, obsoletely notched, or produced into « shorter or longer canal ; 
inner lip generally, outer lip occasionally, plaited. 
The opercula of the living genera are narrow, elongated, horny, sub-spiral, with 
a notch on the internal side. The animals have a smal! foot without or with a small 
operculiferous lobe, short and anteriorly folded tentacles, which are thickened at 
the base, and have the eyes on the internal edges near the basis, sessile or on thick 
bulgings.. The teeth are said to be wanting or rudimentary. The proboscis is figured 
by Quoy and Gaimard (Voy. Astrolabe, Atlas Pl. LXVIT) trumpet shape, of a form 
very similar to that of Zerebra (ibid. Pl. XXXVI, Fig. 17). The mantle is generally 
provided with a distinct siphonal fold. Some of the living animals, of Obeliscus at 
least, must have a short produced siphon and turned upwards, otherwise it would 
be impossible that such a distinct ridge with insinuated striee of growth could be 
formed at the anterior termination of the last whorl, as can generally very dis- 
tinctly be observed in Obeliscus, and in Pyramidella very often also. On this 
account, supported by the weil developed anterior canal in the fossil Nerinee (and 
thus allowing a conclusion as to a relatively greater development of the sipho), we 
think it advisable to retain this family in the StpHonostomata, as long as this latter 
tribe of CrENOBRANCHIA cannot easily be replaced by some better arrangement. 
It is true that the genera Odostomia, Turbonilla, and others can in no way be 
sufficiently characterized as SIPHONOsTOMATA, but according to what is known 
about the animals of all the different genera, they appear to be so thoroughly 
identical, that it is impossible to keep them separate. There is, as I have already 
mentioned, some kind of disharmony and evident insufficiency in every systematical 
attempt. 
