212 
i With these were found many specimens of two other 
‘forms—one like a very minute Dentalium of about the same 
length, much narrower at its posterior end, which is provided 
with a similiar spine projecting from the convex side. The. 
‘anterior end is fractured. The other form gradually in- 
creases to a diameter just about equal to that of the posterior 
end of the Cadulus, then contracts, and then expands again, 
and gradually attains the diameter of the middle of the 
Cadulus; here it is fractured. These appear to be three pro- 
gressive stages of its growth—first, as a Dentalium-like shell, 
which becomes constricted when it reaches a certain age, then 
begins to form the proper Caduius shell, from which it sub- 
sequently breaks off, leaving the tiny projecting spine beyond 
the line of fracture. 
Type in Dr. Verco’s: collection. 
Cadulus spretus, Tate and May. 
Cadulus spretus, Tate and May, Trans. Roy. Soc., S.A., 1900, 
vol. xxiy., p. 102. Type locality—Port Esperance, Tasmania, in 
24 fathoms (W. L. May); Tate and May, Proc. Linn. Soc., 
N.S.W., 1901, vol. xxvi., p. 420, pl. xxv., fig. 52; Hedley, 
Memoirs Austr. Mus., 1903, vol. iv., p. 328, in 41-75 fathoms off 
coast of New South Wales; also 5 fathoms in Dusky Sound, New 
Zealand; Hedley and May, Records Austr. Mus., 1908, vol. vii., 
No. 2, p. 118, in 100 fathoms off Cape Pillar, Tasmania. 
Dredged in 55 fathoms north-west of Cape Borda, 5 
good; in 62 fathoms north-west of Cape Borda, 36 good; in 
90 fathoms off Cape Jafia, 6 good; in 110 fathoms off Beach- 
port, 6 good; in 130 fathoms off Cape Jaffa, 18 good; in 
150 fathoms off Beachport, 20 moderate; in 300 fathoms off 
Cape Jaffa, 1 poor. These are identical with cotypes sent to 
me by Mr. May. 
At the following localities and depths a modified form 
was dredged:—Sixty-two fathoms north-west of Cape 
Borda, 3 good; in 90 fathoms off Cape Jaffa, 22 
ood; in 110 fathoms off Beachport, 3 good; in 
130 fathoms off Cape Jafia, 2 good; in 150 fathoms 
off Beachport, 5 good and 3 moderate. These have 
at one point in their length a sharp annular constriction, 
beyond which the shell often has a slightly altered axis, and 
at times a somewhat different curve. The relative length of 
the two portions varies; the earlier or the later part may 
form nearly the whole, or there may be any intermediate 
proportion. No complete Cadulus similar to 0. acuminatus, 
Tate, was taken in these dredgings. Mr. May says that in 
the type locality, where several dozen cotypes were taken, no 
C. acuminatus, Tate, were obtained. Yet the constriction 
at the anterior end of (. spretus suggests that it is only the: 
