126 BULLETIN OF THE BUREAU OF FISHERIES. 
proved by keeping some of such crabs until spawning season and finding that spawning 
ensued. 
13. A female crab may lay two and probably more batches of eggs during the 
course of her life, the spermatozoa from the one copulation sufficing to fertilize suc- 
cessive lots of eggs. This was proved both by microscopic examination and by experi- 
mentation upon crabs which were known to have laid at least one previous batch of 
eggs. The female crab dies shortly after having laid the last lot of eggs. Death 
usually occurs in the late summer or autumn. 
14. The general habits are discussed, including walking, swimming, methods of 
concealment, feeding, etc. The majority of the crabs do not bury in the substratum 
during the winter but lie on the bottom in the deeper water in a more or less dormant 
state. 
15. The usual term of life of the crabs is probably about three years. 
EXPLANATION OF PLATES. 
PLATE XLVII (Frontispiece). 
(Drawn by Mrs. W. P. Hay.) 
Above.—Female crab immediately after having molted and acquired the broad abdomen. The 
coloring of the crab is most marked while the individual is yet soft. 
Below.—At the left (upper) two outer segments of swimming leg of immature peeler crab, showing 
the pink line which is the ‘‘sign’’ most commonly used to distinguish peeler crabs; (below) portions 
of arm of claw showing distinctive markings of the peeler; at the right, abdomen of immature female 
crab in peeler stage showing the reddish hue assumed at that stage. 
Pirate XLVIII. 
Fig. 1. Mature egg taken from ovary of blue crab. Stained to show nucleus. A, nucleus; B, 
yolk cells.. 280. 
Fig. 2A. Outer view of basal portion of left intromittent organ. B, coxopodite of leg; C, vas 
deferens, continued by dotted lines behind upright portion of organ and entering as shown in 2B; 
D, basal portion of anterior section of organ; E, posterior section of organ, attached to succeeding 
abdominal segment; F, spur on posterior section, fitting into socket in anterior. Natural size. 
Fig. 2B. Inner view of anterior section of intromittent organ, showing manner of vas deferens and 
continuation of the organ into the long copulatory portion. Natural size. 
Fig. 3. Reproductive organs of immature female, with triangular abdomen. A, sperm sacs; 
B, ovaries; C, digestive gland; D, stomach. 
Fig. 4. Reproductive organs of adult female shortly after copulation, showing enlarged size of 
sperm sacs. Lettering as in figure 3. 
Fig. 5. Empty shell from which egg has hatched. 280. 
Fig. 6. Sperm sac of female after jelly which carried spermatophores from the male into it has 
disappeared, leaving the spermatozoa in the white ridge, A. B, anteriodorsal opening to ovary; 
C, opening to oviduct. Natural size. 
Fig. 7. Small portion of sponge, showing manner of attachment of eggs. A, hair; B, covering of 
hair and tendril. Unmstained. X28o. 
Fig. 8. Spermatophore in which the spermatozoa are carried from the male to the sperm sacs of 
the female. 280. 
Fig. 9A. Spermatozoa from vas deferens of male, after treatment with Bouin’s fixing fluid and 
mounting on slide. 
