140 
cially at their upper inner part, and are notched at their 
lower inner angle to form two small cusps. The marginals 
are not quite so large, are rhomboidal plates, and quite 
simple in outline. The laterals are very different from the 
rather remarkably shaped denticles of U. propinqua, figured 
in Man. of Conchology, vol. xvu., pl. xxxix., fig. 11. 
Leiopyrga octona, JZate. Wi / 
Trans. Roy. Soc., 8. Aust., vol. xiv., 1891, part ii.,/p.~ 260, pl. 
xi., fig. 5. 
Dredging has supplied some living examples of this species, 
from which the operculum and radula have been obtained. 
The operculum (pl. xxvi., fig. 15) is horny and multispiral, five 
or six revolutions, with central nucleus. To the margin of 
the spirals is attached a thin membrane, rather less than half 
as wide as the spiral. It is radially striated with slightly 
wavy lines. From the earlier whorls it is absent, doubtless 
worn away, and is fragmentary and ragged on the next to the 
last whorl. The radula (pl. xxvi., figs. 16, 17, 18) has for its 
formula oC (5°15) « . As the examples had been allowed 
to dry instead of being preserved in spirit, the radula was 
difficult to isolate, and not in perfect condition. There is a 
rachidian tooth nearly circular or quadrate, with a slight cen- 
tral projection of the free edge. Then follow five laterals on 
each side, with a thickened outer border, and with the free 
upper margin bent over throughout its whole extent. These 
eleven central denticles have no serrations. Then follow 
short, stout uncini, which gradually become longer and nar- 
rower, and finally are subulate. The number of these mar- 
ginals is indefinite. They have about half a dozen minute 
serrations near their free end. These are not shown in 
fig. 18, though seen in fig. 17. 
The operculum and radula of this species determine its 
location in the Zrochide, and not in the Turbinide, and 
close to Bankivic. Fischer, Manuel de Conch., 1887, p. 810, 
places “Liopyrga”’ as a genus provisionally in the vicinity of 
Phasianella with the remark, “the operculum is unknown.” 
Pilsbry, in Manual of Conchology, vol. xi., p. 10, 1889, 
makes it a section of Bankivia, and at p. 139 refers to “the 
thin, membranaceous 7J'rochus-like operculum” and “‘the teeth 
like those of Margarita,” in Watson’s description of the ani- 
mal of L. picturata, H. & A. Adams. Our species has the 
same characters and should haye the same place. It is quite 
possible it should have the same name. Tate diagnoses 4. 
octona from L. picturata by three features: its conspicuous 
cinguli, its convex whorls, and its linear suture: But its 
cinguli vary in validity; in some examples they are valid in 
Se a 
