104 CRETACEOUS GASTROPODA 
XXII. TURRICULA, Klein, 1753. 
(Vide Adams’ Gen. I, p. 175, Chenu’s Man. I, p. 194.) 
This genus ought to be restricted for fusiform shells with a much produced 
anterior canal only, in which character they stand next to the FuscroLaripa. 
The number of plaits varies from three to five. 
It would probably be better to form a new generic group for those cretaceous 
species, of which Mitra cancellata, Sow. (id. D’Orb., Binkh. a. 0.) Mit. Vaelii, 
Binkhorst (Monog. pl. V,** fig. C,), the here noted South Indian, and other forms 
may be considered the types. They differ from the great number of species of 
Turricula by a more produced and attenuated canal; but as the margin of the outer 
lip has not been in any of those species traced perfect with full certainty, and as 
through the loss of this the above-mentioned difference becomes undoubtedly more 
exposed, it may for the present not be advisable to anticipate that distinction. 
Most of the cretaceous species described as Mitra belong to this generic group. 
1. TURRICULA ARRIALOORENSIS, Stoliczka. Pl. IX, Figs. 15 and 16. 
Turr. testa fusiformi ; anfractibus prope planis, transversaliter costulatis, spiraliter 
striatis ; costulis 14-20 in wno circuitu, parum curvatis, in superioribus nonuunquam 
obsoletis ; striis planis, latioribus atque angustioribus alternantibus ; apertura angus- 
tissima; canali antico moderate longo, attenuato ; labio quadriplicato. 
Spiral angle 32°—35°; sutural angle OF. 
The whorls are nearly flat and ornamented with from 14 to 20 transverse ribs, 
which are slightly curved on the last whorl, the upper portion of each rib—remaining 
visible on the upper whorls—being straight or even bent in the opposite (to the right) 
direction. Numerous spiral strise and suleations respectively cover the surface, 
they are generally alternating, unequal in width, but on the transverse ribs very 
slightly marked. The finer ornamentation of the shell varies a great deal and seems 
to depend very much on the state of preservation. Occasionally specimens are met 
with, which have a larger number of transverse ribs, in which case they usually be- 
come quite obsolete on the uppermost whorls. When in addition the spiral striation 
is a little more sharp, such specimens have then a great resemblance to JJ. cancel- 
lata, Sow.,* but I have never observed any granulation on the surface of the Indian 
shell, and even when the ribs are sometimes more numerous than is shown in the 
figured specimens, the spiral strize remain apparently always faintly marked. The 
anterior portion of the canal is prolonged and rather thin, as in JZ. cancellata ; 
the inner lip has four oblique folds, the anterior ones being thinner. 
Locality —Near Comarapolliam in Trichinopoly district. 
Formation.—Arrialoor group. 
* D’Orbigny separates (Prod. IL, p. 154) the WM. cancellata, Sow. of the Pal. franc. as distinct, under the 
name of VM. Cassisiana, evidently on account of there being only three folds represented in the figure of the 
French species. It is possible that he is right, but certainly it would be a singular case of a Mitra, if his 
specimen had no other fold on the whole space between the three folds marked and the termination of the 
canal. D’Orbigny’s specimen as figured exhibits otherwise no distinctions from the Gosau species, and I believe 
they are identical. 
