Vv EPICARIDA—LIFE-HISTORY OF DAWNALIA Ii 
which is itself parasitic on the spider-crab, Znachus mauritanicus, 
at Naples. The adult Danalia is a mere curved bag full of eggs 
or developing embryos, and without any other recognisable organs 
except two pairs of sper- 
mathecae upon the ventral 
surface where the _ sper- 
matozoa derived from the 
larval males are stored. 
In Fig. 86 is repre- 
sented a female of Jnachus 
mauritanicus Which carried 
upon it two Sacculinae and 
a Danalia curvata, and 
upon the latter are seen FIG. 86.—Inachus mauritanicus, 2, x1, carrying 
: two Sacculina neglecta (a, 6), and a Danalia 
two minute larval males curvata (c), the latter bearing two dwarf males. 
in the act of fertilising the 
adult Danalia. The eggs develop into the Epicaridian stage, 
after which the larva passes into the Cryptoniscus stage (Fig. 87). 
In this larval form the segments are clearly delimited ; the only 
mouth-parts present are the mandibles, but there are seven pairs 
of thoracic limbs and the full number of 
pleopods. This Cryptoniscus stage is found in 
all the Epicarida, and only differs in detail in 
the various families. 
In the Cryptoniscina the Cryptoniscus larva 
is the male, and at this stage possesses a pair 
of large testes in the thorax. The ovaries are 
also present at this stage as very small bodies 
apphed to the anterior ends of the testes. The 
larval males in this state seek out adult fixed 
Danaliae and fertilise them; and, when this is 
accomplished, they themselves become fixed to 
the host and begin to. develop into the adult 
Fic. 87.—Ventral view female condition. The limbs are all lost, and 
eT ei out of the mouth grows a long proboscis (Fig. 
curvata, 8, x 25. 88, P), which penetrates the tissues of the 
host. The ovaries begin to grow, and a re- 
markable process of absorption in the testes takes place. These 
organs, when fixation occurs, are never empty of spermatozoa, 
and are frequently crammed with them. After fixation some 
