206 NATICIDA. 
AmAuvROoPs!Is, Morch. Shell with canaliculated sutures. Scarcely 
distinct from Amaura. NN. canaliculata, Gould (1xiii, 50). 
AMAURELLA, A. Ad.,1867. Shell small, ovate, imperforate, white, 
shining, apex submammillary ; aperture acuminately ovate ; lip 
arcuate, simple, thick. 3sp. Japan. N. Japonica, A. Ad. 
LARINA, A. Adams. (Robinsonia, Nevill.) Shell thin, delicate, 
composed of a few rapidly increasing whorls; not umbilicated, 
columella simple, lip not reflexed. Epidermis olivaceous. 
Operculum horny, annular. Somewhat resembles Amauropsis. 
6 sp. Indian Ocean, Australia. N. Ceylonica, Nevill (1xili, 51). 
This is possibly a fresh-water shell, and perhaps belongs in 
Paludinidee. 
NATICOPsIS, M’Coy. (Neritomopsis, Waagen, 1880.) Shell 
imperforate ; inner lip very thick, spreading. Operculum shelly. 
Carboniferous Limestone; Great Britain. N. Phillipsii, M’Coy 
(xiv, 67). 
ISONEMA, Meek. (Section of Naticopsis.) J. humilis, Meek 
(xiv, 71). Devonian; Ohio. 
TRACHYDOMIA, Meek and Worthen, 1866. (Section of Nati- 
copsis.) Surface covered by small regularly disposed tubercles. 
N. nodosa, M. and W. Carboniferous; Illinois. 
EUsPIRA (Agassiz), Morris and Lycett. (Holopea, Hall, in 
part.) Spire more or less elevated; whorls few, distinct, angu- 
lated or carinated. Inferior Oolite; England. ‘ Euspira presents 
considerable affinities to the Paleozoic genus Scalites, Hall, in 
the lines of growth having the appearance of a slight fissure, 
where the angle occurs in the volution.”—Morr. and Lyc. W. 
canaliculata, Morr. and Lye. (lxiv, 84). 
GYRODES, Conrad, 1860. 
Distr.—Cretaceous; U.S., Europe, India. G. alveata, Conr. 
(Ixiv, 70). 
Shell depressed-globose; aperture generally angular or nar- 
rowly rounded below; inner lip thin; umbilicus wide, deep, 
without callosity, bounded by a revolving carina which is some- 
times crenate, with occasionally a second small revolving ridge 
within ; whorls shouldered above, the angle generally wrinkled 
or crenate. ; 
CrovuGcHtTontiA, Hudleston. 
Distr.—C. (Phasianella ) cincta, Phillips. Oolite; England. 
Shell short, conical and solid, with a widish base; whorls 
about five, flat and angular; body-whorl more or less bicarinated 
with slight depression of the intervening space ; aperture ovate 
to ovate-oblong, rounded anteriorly ; pillar nearly straight, with 
little or no callus. 
This group seems to occupy an intermediate position between 
Natica and Chemnitzia. 
