OF SOUTITERN INDIA. 29 
number of transverse ribs is nearly constant, 15 in one volution, and that of the spiral, 
7or8 on one whorl. Of the latter the upper three are more distant from each other 
and usually stronger, the lower 4—5 are thinner and much more closely placed to 
each other. There are sometimes exceptional cases met with, in which the lower strize 
are of equal strength with the upper (vide Fig. 3), or where the upper become even 
nearly obsolete, while the lower continue in their strength. When the shell surface is 
completely preserved, it is also covered with a very fine spiral striation. 
The last whorl is somewhat inflated, in cirewmference triangularly gibbose and 
near the middle provided with a strong keel, which is tuberculose or nodulose : 
the nodules being produced by a stronger development of the transverse ribs; 
the keel continues, however, smooth on the wing-like prolongation of the outer 
lip. The aperture is considerably narrowed from the great callosity of the inte- 
rior of the lips. The posterior canal is short, not extending usually beyond the 
antepenultimate whorl. In none of our specimens is the anterior canal preserved, it 
could not, however, have been long, and is probably complete in the figure given 
by Professor Forbes (loc. cit.), according to which we have restored it in outline in 
our Hig. 2, PL II. The wing is simple and narrow, turned upwards or poste- 
riorly, internally canaliculated in its entire length and externally keeled near the 
upper, or concave margin. Between the wing and the anterior canal there are two 
insinuations of the margin, being separated by a small pointed prolongation of the 
same, so as to form a second small wing. 
There cannot be a question, that Professor Forbes’ figure, referred to above, 
represents only a fragment of a very large specimen, being mostly devoid of shell- 
surface (vide Fig. 4, Pl. IT.). We have observed, that on similar large specimens 
the ornamentation often becomes near the aperture more or less obliterate, although 
it does not disappear without leaving traces of roundish tubercles. Prof. Forbes says, 
that the surface appears to have been quite smooth, but that it was not, is distinctly 
seen in his figure, which shews the three upper spiral strize as impressions on the 
interior side of the uppermost whorl. 
Ap. securifera bears, as regards ornamentation and general form, a great resem- 
blance to Rost. Requieniana (D’Orb. Pal. Frang. Ter. cret. I. p. 298, Pl. 209, 
Figs. 3 and 4). The spiral striation of the latter does not seem to have been well pre- 
served on the specimens, from which the figure was restored; but that it could not 
have been wanting on the lower or anterior portion of the younger whorls is sufficient- 
ly proved by its existence on the last. It is difficult to say, until actual specimens 
have been compared, that they are identical, but certainly it appears very probable, 
that they do not belong to actually different species. The Ap. granulata, Sow. sp. 
(Zekeli, Gosau-Gastropoda, Pl. 12, Figs. 3, 4,7 and 8: Alaria id. Stoliczka, Sitzungsb. 
Akad. Wien. Vol. LIT, p. 67) differs merely by its posterior canal being prolonged to 
the apex and by some of the transversal ribs being at intervals considerably thickened. 
It belongs undoubtedly to the same group of species of Aporrhais. , 
Localities. Kolakonuttom, N. of Serdamungalum, N. of Alundanapooram, 
E. of Anapaudy, Andoor, N. HE. of Koloture; Olapaudy, Arrialoor and Karapaudy. 
I 
