94 
PACIFIC SCIENCE, Vol. IV, April, 1950 
13 x 20 mm. Thousands of ova, which in this 
species were quite small (0.14 mm.), were 
contained in a capsule (Fig. 14 a-d) . Early 
cleavage stages only were observed. Numer- 
ous polar bodies were seen with them. 
0.1 mm. 
0. 1 mm. 
Fig. 14. Conus sumatrensis Hwass. a, Egg cap- 
sules attached to rock; h-d, cleavage stages show- 
ing polar bodies; e, free-swimming larva, ventral 
view. 
After 4 days of incubation the embryos 
began to show activity and a shell had begun 
to form. After 7 days the anterior end of the 
embryo had assumed a trilobular form with 
short cilia. A shell covered the greater part 
of the body. On the twelfth day of incubation 
the young began to leave their capsules, en- 
tering upon their free-swimming larval stage. 
The veliger lobes were rounded and pig- 
mented with green as in C. hebraeus, but 
unlike the larva of that species, a rounded 
foot, with an operculum projecting beyond 
it, was present. The shell, which measured 
0.25 mm. in length, was covered with a fine 
granulation (Fig. 14^). 
Conus abbreviatus Nuttall 
Fig. 15 
On March 15, 1923, a dozen egg capsules 
Fig. 15. Conus abbreviatus Nuttall. Egg cap- 
sule attached to rock. 
were deposited by a Conus abbreviatus which 
had been isolated in the laboratory. The cap- 
sules averaged 8x10 mm., had firm and rigid 
walls with smooth sides and margins, except 
for the distal margins, which were slightly 
corrugated (Fig. 15). A slight reddish tinge 
was discernible. Cleavage and larval devel- 
opment were not investigated. 
The egg capsules of Conus have not been 
of uncommon occurrence in the shallow water 
of the Waikiki reef near the Marine Biolog- 
ical Laboratory. Several different forms have 
been found and specific distinction could 
often be made by the differences in size, shape, 
and firmness, and perhaps to some extent by 
color. A comparison between ova and veliger 
larvae of a few unidentified capsules, with 
ova and veligers of determined species, has 
shown a corresponding distinction. In other 
words, specific characters may be recognized 
in the egg capsules. 
The capsules in all the species under ob- 
servation had tough parchment- like walls 
with more or less corrugated borders. A slit 
through which the young might escape when 
they reached the free-swimming stage was 
present at the distal end of the capsule. Dur- 
ing incubation this slit was closed by a clear, 
semi-transparent substance which then ap- 
peared as a window. My observations have 
not convinced me that the young may not 
also be released by a rupture of the capsule. 
The following species of Conus have been 
found in the living state within wading dis- 
tance of the Marine Laboratory: 
C. abbreviatus Nuttall 
C. catus Hwass 
C. flavidus Lamarck 
