165 CRETACEOUS GASTROPODA 
XLIT. NARONA, #. and A. Adams, 
is distinguished by a much produced canal with attenuated termination, two prin- 
cipal columellar folds and crenulated margin of the outer lip; the forms united by 
HH. & A. Adams under this name being very peculiar and different from the other 
sub-genera of Cancellaria, we do not hesitate to accept the same as a genus. 
1. Nanrona (CANCELLARIA) EXIMIA, Sfoliczka, Pl. XIII, Figs. 15 and 16. 
Nar. testa ovata, spira brevi, acuminata; anfractibus quinis, convexis, duobus 
primis minimis, levigatis, ceteris lineis spiralibus tmpressis atque costis transversali- 
bus, crassis ornatis ; lineis equidistantibus, numerosis, interstitus latioribus separatis ; 
costis inter se equalibus, rectis, circiter duodenis in uno circuitu ; apertura obliqua, 
elongate-ovata, utrinque ad terminationes subacuta, antice effusa; marginibus paulo 
incrassatis, labro intus ad marginem crenulato, postice parum insinuato ; labio valde 
calloso, arcuato, antice biplicato, postice umiplicate-dentato; canali moderate pro- 
longato, lateraliter quoddam curvato. 
Spiral angle 70°—80° ; sutural angle 7°—8°. 
Height of last whorl : total of shell (considered as 1:00) ... 069—0°76. 
This very fine shell consists usually of five strongly convex volutions, the last of 
which is always the most inflated, the height of the spire varying from 24 to 31 
hundredths of the total height of the shell. The two uppermost whorls are very 
small, flattened (not inflated as usually in species of the Vozurr), but smooth ; 
the others are spirally sulcated and transversally ribbed. The sulci, or rather only im- 
pressed lines, are separated by interspaces, broader than their own width, while the 
same are between the transverse ribs very nearly equal to the thickness of the latter. 
The great regularity in the ornamentation, combined with the peculiar form of the 
shell, appear to be very constant characters of this species. 
The aperture is placed obliquely to the axis of the shell, ovate, being pointed on 
each end and provided anteriorly with a notch in consequence of the prolonged canal ; - 
both margins are posteriorly united; the outer sharpened on its edge, thickened 
interiorly and denticulated, having near the posterior termination a slight sinuosity, 
although this barely affects the straightness of the transverse ribs; the inner lip 
is in its entire extent much thickened, posteriorly somewhat expanded with a short 
fold on the inner side, and anteriorly with two equal but not strong, very oblique, 
folds, which extend over the entire columella; the latter is solid; the canal pro- 
duced, somewhat laterally bent, and very slightly recurved. This last peculiarity of 
the produced canal, the great thickness of the inner lip with two anterior equal 
folds, and the short posterior fold, as well as the solid structure of the shell bear 
decidedly a more striking resemblance to the Caycrnzari than to the Vozurm2, 
to which otherwise this species could be referred. 
The only fossil which I am aware of, and which, as regards its general form, 
bears some resemblance with our species is Voluta Melo, Schafhzeutl (Siid-Bayerns 
Leth. geognostica 1863, p. 203, Pl. XLIX, Fig. 5). The specimen is said to have been 
