26 
of the shell. Stomachs examined during this 
period contained large quantities of barnacle 
fragments, fragments of the common mussel, 
Mytilus edulis, and also small quantities of hy- 
droids and bryozoans. Apparently this crab be- 
comes quite carnivorous during periods when 
the large brown algae are absent from its typical 
habitat. 
During feeding operations this species uses 
the walking legs to hold on to the algae and the 
chelapeds to cut bits of algae and transfer them 
to the mouth parts. Large fragments are swal- 
lowed whole and are later ground up by the 
gastric mill within the stomach. When feeding 
on barnacles the chelapeds are again used. The 
movable finger is inserted into the open edge of 
the barnacle and the shell is pried outward, thus 
breaking the side of the barnacle’s case. The 
shell then becomes dislodged from the piling 
and the tissue is devoured. Presumably small 
mussels are broken in a similar manner. In the 
laboratory one could not help but notice the 
keen visual awareness of this species as food 
was placed in the aquarium. Algae and cut fish 
alike were caught in mid-water as they sank 
past the crabs. The slightest movement of food 
seemed to attract the attention of crabs quite 
some distance away in the tanks. Cut fish that 
was secretly placed in the tank, however, would 
go unnoticed for some time. This suggests that 
sight and the tactile senses are most highly 
developed for feeding, and that the chemical 
sense is not very extensively used. 
REPRODUCTIVE ACTIVITY: Garth (1958:192), 
in his discussion of breeding of P. producta, 
states that gravid females were commonly found 
at Coos Bay, Oregon, in June and July; in So- 
noma County, northern California, from Oc- 
tober to February; and at Dillon Beach, Marin 
County, in August and November. In southern 
California females with ova have been taken 
from November to February and in lower Cali- 
fornia in January, March, and June. In our own 
collecting, field encounter of this species ranged 
from a few up to about 18 females each month, 
except during May, September, and October, 
when we were unable to locate any females of 
this species. Females carrying eggs were found 
during every month of the year with the ex- 
ceptions noted above. Moreover, except in No- 
vember and December, all females examined 
PACIFIC SCIENCE, Vol. XVIII, January 1964 
each month had eggs. This species seems to be 
omni-seasonal in its egg production, but there 
is a trend of egg deposition beginning in No- 
vember and December and becoming more ap- 
parent in the month of January. This is fol- 
lowed by an embryonic development during 
March, April, and May. Some extremely new 
eggs are found again in April, July, and August 
with hatching in August, February, and April. 
Since none of the field animals observed from 
month to month were tagged, it would be con- 
jecture to say whether two broods of eggs are 
produced annually. Laboratory data seem to in- 
dicate that the development of a single brood 
requires the greater part of the year. 
PRODUCTIVITY: Eggs within the egg masses 
of 11 individuals were counted to determine 
the size of an average brood. The hepatic cara- 
pace width of these specimens ranged from 41 
mm to 56 mm; and the number of eggs per 
mass varied from 34,000 to 84,000, with an 
average of 61,000 eggs per brood. New eggs 
are bright orange and progress to a very deep 
red before part of the embryo becomes hyaline 
and deep purple. At this time the eyes begin to 
show and there is a reduction in the amount of 
purple material within the egg case. The egg 
mass appears somewhat grayish-purple at time 
of hatching, due to the hyaline interior, eye 
spots, and purple pigmentation. 
COPULATION: At no time was the process 
of courtship and/or copulation observed for 
P. producta. The process is probably similar to 
that as described for P. gracilis. On several oc- 
casions in the field we observed what appeared 
to be the onset of copulation: pairs of Pugettia 
producta were seen on pilings, going through a 
wrestling motion which resembled the begin- 
ning of copulation. The animals were situated 
with one individual above the other, each facing 
the other. Repeatedly, as we continued to ob- 
serve this process, the lowering tide would inter- 
rupt the activity. The pair would then move 
farther down on the piling and resume this 
"grappling” motion, but before copulation could 
begin the tide would again interrupt. The pair 
was finally forced to leave the piling and move 
out on the sandy substrate. These animals prob- 
ably copulate either on pilings or on the large 
bladder kelp at night, but are probably more 
secretive about it than other species. 
