438 Prof. F. M‘Coy on two new Fossil Cowries. 
beds, with which latter it agrees better in its usually naked 
sulcus; but the ends of the ridges are never dilated, and, in 
addition to the same differences of the more arched mouth and 
less inflected outer lip of the Australian species, the shell in it 
is larger, thinner, and the ridges more elevated, thinner, and 
further apart. 
Very common in the blue Tertiary clays and limestone be- 
tween Mount Eliza and Mount Martha in the Bay. Very rare, 
but of large size, in the blue clays of Muddy Creek near Grange 
Cwm, five miles from Hamilton. 
Cyprea gigas (M‘Coy). 
Sp. Ch. Shell very large, thick; form ovate, back very gib- 
bous, somewhat spheroidally irregularly rounded ; base flattened 
oval, much thickened, extending slightly in thick obtusely 
rounded margins on each side of the anterior and posterior ends 
of the shell (not in the middle) ; inner lip rounded, smooth 
within, flattened near the anterior channel, slightly concave 
before joining the tumid outer margin; outer lip inflected, 
tumid, broad, and.the edge smooth in the middle, with nine or 
ten nearly obsolete obtuse teeth near the anterior end, and a 
few still fainter near the posterior end. Aperture narrow, mo- 
derately curved, widest towards the anterior end, terminating in 
deep narrow channels at each end, the anterior one reflected at 
an angle of about 70° from the base, projecting upwards, form- 
ing a reentering angle of 65° with the back, the posterior chan- 
nel reflexed at upwards of 140°, obliquely subtruncate, inclining 
forward, and adherent to the spire. Spire exposed, of two 
whorls; apex obtuse, large; surface smooth. Length of large 
specimens 8 inches, proportional width 5°7,, height +35, height 
of anterior channel 533;, of posterior one -;2,4;, diameter of spiral 
suture at base of spire 71,4, width of middle of mouth +4. 
This gigantic species far exceeds any known cowry in size, 
and, like the large Eocene Tertiary C. tuwberosa, is so completely 
destitute of teeth on the inner lip as almost to belong to Ovula. 
With the very oblique light of a candle, or by a delicate sense 
of touch, faint indications of teeth may be detected, but scarcely 
more than, under similar circumstances, may be found in the 
recent Ovula ovum. The flattened base and thickened inner lip 
forming an obtuse lateral projection at each end of the shell, 
as well as the strong reflection of the channels, induce me to 
place the present fossil in Cyprea. 
In blue clay of Muddy Creek, ten miles south of Hamilton, 
and in similar beds between Mount Eliza and Mount Martha. 
on the shores of Hobson’s Bay. 
