OF SOUTHERN INDIA. 201 
12. Crerrratum (EXELISSA ?) scALAROIDEUM, Forbes. Pl. XV, Figs, 6 and 7. 
1846. Cerith. scalaroideum, Forbes, Trans. Geol. Soc. Lond., ser, II, vol. VII, p. 125, Pl. XIII Fig. 7. 
Cerith. testa turrita; anfractibus circiter denis, planatis, suturis latis atque 
profundis sejunctis, transversim 14-16-costulatis, spiraliter 4-liratis: liris tenuibus 
atque im costulis tubercula plus minusve elata seu acuta formantibus; superficie omnina 
spiraliter minutissime striata; costulis prope aperturam in striis numerosis elevatis 
dissolutis ; apertura circulari, marginibus conjunctis, paulo elevatis, antice canali brevi 
atque angustissimo, contorto terminantibus ; basi ultimi anfractus prope peripheriam 
bicarinata, ad medium excavata atque prope terminationem canalis unicarinata ; 
carius omnibus crenulatis, crassis. 
Spiral angle (on the top whorls only) 30°—82°; sutural angle 12°—14° 
Height of last whorl : total of shell (considered as1-00)  ... ae Eee O42, 
» of penultimate whorl : height of spire (considered as 1:00) eas Ov2D) 
” ” ” oe its width ( ” ” ” ) pee 0-47 
The shell begins to grow with an angle of about 32°, but after it has reached 
a certain size, the whorls do not increase to the same extent proportionally in 
width, and the form becomes therefore more cylindrical. The transverse ribs 
are always thin, oblique in the direction of the outer lip, and near the aperture 
they become replaced by a large number of merely elevated lines. Their number 
varies between 12 and 16; 14 being about the usual number. Spiral ridges 
seem to be always only four; the tubercles, which are formed by them in crossing 
the transverse ribs, are generally sharpened and pointed, seldom they appear so 
much rounded, as represented in our Fig. 6, Pl. XV. The entire surface of the 
shell is minutely spirally striated. The aperture is circular, its margins somewhat 
elevated and separated from the other shell, forming a kind of a tube and terminating 
anteriorly with a short, contorted, and exceedingly narrow canal. 
I need scarcely repeat here again, what I have already stated at length about 
Piette’s genus Hvelissa. The only species that has really a very great resemblance 
to our Indian fossil is one figured and described by Reuss (Boehm. Kreide. 1846, 
Pt. I, p. 42, Pl. X, Fig. 5, and Pl. XI, Fig. 22) as Cerith. reticulatum (>? Sow.*) from 
the cretaceous conglomerate of Meronitz in Bohemia. I would almost believe that 
they are identical. Geinitz identifies that C. reticulatwm of Reuss with Cerith. 
imbricatum, Geinitz,+ (vide Quadersandsteingebirge, 1849-50, p. 142), but upon a 
reference to Geinitz’s original figure in his “Characteristic des Sxechs. Boehm. 
Kreidegeb.” Pt. IIT, 1842, p. 72, Pl. XVIII, Fig. 22, such an identifieation is very 
objectionable, unless Geinitz’s figure be quite incorrect. This specimen of Cer. 
imbricatum has the whorls separated by very narrow sutures, the transverse ribs are 
* The name C. reticulatwm has been used repeatedly by several authors, as Montagu, Risso, Deslon- 
champs, a. 0. F 
_ + This name cannot stand, for it has been equally used a long time ago by Bruguiere, Bonelli, and others. 
Miinster’s Cerith. imbricatum (in Goldf. Pet. Germ.) is called by Geinitz, C. Goldfussi (non idem, Zekeli,)=C. reti- 
cosum, Sow. (vide Stoliczka in Sitz. Akad. Wien, 1865, Vol. LII, Revision, etc., p. 97). D’Orbigny, in Prod- 
rome LI, p. 231, calls the same C. sub-imbricatum. 
3D 
