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OF SOUTHERN INDIA. 12 
XXV. TRITONIDEA, Swainson, 1840. 
1. Trrronmea erBposa, Stoliceka. Pl. XI, Fig. 5. 
Trit. testa elongata, ad medium gibbosa, utrinque acutiuscula ; anfractibus octonis, 
primis duobus minutis, levigatis atque politis; (im specimine cyaneo-coloratis), 
sequentibus convexis, prope suturam multo angustioribus, spwaliter dense striatis, 
infra transversaliter tuberculato-costatis; spira brevi, acuta; ultimo anfractu 
latissimo, gibboso, costis ad medium convewitatis crassis, tuberculosis, striis supra et prope 
suturam tenuioribus ; canali spire sub-equali, paulum lateraliter atque supra recurvo ; 
labio antice calloso, postice tenui ; labro acuto, margine wundulato, intus sulcoso. 
Angle of the spire (excepting the last whorl) 35°; sutural angle 6°. 
Height of last whorl : total of shell (consd. as 1-00) a Ode 
The great number of whorls, being strongly contracted on the suture and the 
ast being more than twice as wide as the penultimate, but rapidly narrowing 
on the anterior extremity again, give this shell a very characteristic form, which, 
combined with the ornamentation and the shortness of the canal, recalls very much 
the similarity of some species of the family Tezronrp 2. 
The figured specimen is in excellent preservation, and on this the two uppermost 
whorls are perfectly smooth with a blueish tinge; it is probable that this colouring 
is original on the shell. The whorls next to the embryonal are only spirally 
striated, and the transverse ribs do not appear until on the third before last, being 
obsolete near the suture, where the spiral strize are considerably thinner. On the 
last whorl they may be said to form transversally elongated tubercles, ten in 
number. The spiral strie are strongest in crossing these tubercle-like ribs, and 
become towards the anterior extremity broader, but less elevated, and gradually 
obsolete. The strive of growth are distinctly perceptible, but very fine. 
The aperture is somewhat pear-shaped, broadest above and gradually narrowing 
and lengthened anteriorly. The outer lip is sharp, internally grooved; the inner lip 
quite smooth, posteriorly thin, anteriorly somewhat thickened; the canal is laterally 
curved with its termination somewhat turned upwards. Near this termination the 
inner lip is somewhat thicker, forming a very slight fissure exactly similar to the 
largest number of living Tritonidee. 
This species bears evidently considerable resemblance to Fusus Marrotianus, 
D’Orb. (Pal. Frang. terr. crét. Pl. 225, Fig. 2), as regards general form and spiral 
striation, but the smaller number of whorls with a somewhat more obtuse spiral 
angle and the few transverse ribs on each of them appear to justify fully the proposed 
distinction of the two species. J. Miiller (Petref. d. Aachner Kreidef. 1851, p. 34) 
unites the F. Marrotianus, D’Orb. with F. Clementimus of the same author. The 
forms of both and our own species are like enough, but as D’Orbigny’s figure of the 
last-named species represents only a very poorly preserved cast, the question cannot 
be settled satisfactorily without the original specimens. 
Locality—N. of Alundanapooram in the Trichinopoly district; very rare. 
Formation.—Trichinopoly group. 
