114 CRETACEOUS GASTROPODA 
1. HeEmMirusvus cinctus, Stoliczka. Pl. X, Figs. 17 and 18. 
Hemif. testa spira brevi, late conica; ultimo anfractu ad medium inflato, antice 
canalt longo atque recto extenso ; anfractibus senis, ad marginem suturalem twmescenti- 
bus, crenulatis, infra suturam excavatis atque infra excavationem angulatis, postea 
convexiusculis, transversim costatis; costis acutiusculis, antice in ultimo anfractu 
gortim obsoletis ; superficie spiraliter striata, striis crassioribus atque tenwioribus 
alternantibus, antice aliquantisper sub-granulatis ; apertura perlonga, postice latiori, 
antice versus sensim angustiore ; labro acuto, intus sulcato ; labio levigato, tenwi. 
Spiral angle 80°; sutural angle 6°. 
Height of last whorl : total of shell (considered as 1:00) ... 0°73. 
The principal characteristics of this species are the numerous transverse ribs, 
of which there are about twenty-two on the last whorl (their number being higher 
up nearly the same or somewhat less), the thick and obsoletely crenulated posterior 
margin of the whorls and the numerous spiral strive, which cover the entire sur- 
face. These strize usually alternate in strength on the last whorl and are on the 
excavated, posterior, portion generally somewhat thinner. The strize of growth are 
very distinct on the well preserved surface of the shell, and form fine granulations 
on the spiral strive. According to the elevation of the sutural margin and the pos- 
terior angle of the whorls the respective excavation between them is more or less 
deep, but it is always distinctly marked. The outer lip is sharpened and grooved 
internally, the inner lip near the posterior termination a little thickened, and the 
anterior canal long and straight. 
When the surface of the shell is somewhat worn off the finer ornamentation 
disappears and the coarser spiral strize appear more distant and sometimes granulated, 
as seen in Fig. 18, Pl. X; the posterior excavation becomes at the same time more 
obliterate. 
This species so very much resembles in every way the Voluta cincta, Forbes, 
(Trans. Geol. Soc. Lond. VIT, p. 182, Pl. 12, Fig. 6), that I am at a loss to give any 
strict distinctions between them. ‘The number of longitudinal (here transverse) ribs 
and the strength of the spiral ones varying in almost every specimen,’ says Prof. 
Forbes, and this is exactly what may be seen in our specimens. The spiral striz, 
even when less numerous, are always stronger than in the following species, and the 
same is the case with the transverse ribs. The ‘thickened crenulated rim’ border- 
ing the suture is equally well marked in both these similar species. Prof. Forbes 
states, however, distinctly, that the aperture is ‘4—5-plicata’ and certainly he must 
have observed the plaits or something like them, and until this statement is dis- 
proved, or otherwise confirmed, the identification cannot be established. It is to be 
regretted that Prof. Forbes has not given a second view of the specimen, which he 
examined. He further states, that the species occurs also at Trichinopoly, which 
increases the difficulty, as I am unable to assign from our tolerably fair Trichinopoly 
collections any fossil really identical with that of Prof. Forbes. Certain it is, that in 
