OF SOUTHERN INDIA. 159 
keel below the upper principal one, and occasionally in large specimens even a third 
one is indicated; the former remains sometimes perceptible on the suture of the 
preceding whorls, when the spire is more turbinate. 
The transverse ribs are simply the remainders of the margins of the outer lip, 
in no way thickened, and following closely each other like the slates of a roofing. 
On the keels they are more or less elevated, laminar,—probably they were more so in 
the living shell—and placed very similarly to those in the recent species, Tr. bicarinata 
and others. The spiral strize are very numerous and of unequal strength; they are 
less marked, when the transverse ribs are stronger, but when these—in the young 
shell—are very slight, the spiral striation appears the more distinct (see Fig. 9). 
The aperture is oval, very oblique, with flattened and somewhat expanded margins, 
which are posteriorly thicker and united; both are entirely smooth internally 
and there is not a trace perceptible of any fold in the total length of the columella. 
The latter is hollowed out and on the last whorl strongly edged with a lamellar keel, 
terminating at the anterior notch of the aperture (sub-gen. Iphina, H. and A. 
Adams). 
This species attains a considerable size, the largest specimen from Shutanure 
measuring 57mm. in height and 43mm. in width on the last volution. I have al- 
ready noticed the similarity of this species to other tertiary Trigonostoma. There 
can be scarcely a doubt, that our fossil is identical with that described by Miller. 
As it is evident from our figures that the form of the shell varies with the height 
of the spire, there does not remain the slightest character, which could justify the 
separation of the Indian from the European species. Mitller (loc. cit.) exerted 
himself in vain to prove the non-existence of the genus Delphinula, evidently merely 
to find a place for his very remarkable fossil in a generalisation of the character of 
Trochus; but his propositions certainly have no chance of being appreciated by most 
other conchologists, in fact they have remained unnoticed. 
Localities —N. of Kunnanore, E. of Anapaudy, and 8. W. of Shutanure; at 
the former localities the species does not appear to be rare. 
Formation.—Trichinopoly group. 
2. 'TRICHOTROPIS NODULOSA, Stoliczka, Pl. XIII, Fig. 10. 
Trich. testa rhomboidali, spira ultimo anfractui in altitudine fere equali; an- 
fractibus circiter quinis, infra medium rotundate angulatis, ad angulum tuberculatis ; 
superficie spiraliter striata, striis inequalibus, ternis medianis crassissimis ; collumellia 
excavata, levi, antice truncata. 
Spiral angle 80°; sutural angle 8°. 
Height of last whorl : total of shell (considered as 1:00) ... 0:55 
The form of the shell, as a whole, is obliquely rhomboidal, consisting of about 
five volutions only, the last of which does not much exceed the height of the spire. 
The embryonal whorls are not preserved in our specimen; all the others are nearly 
