ARGULUS. 
253 
the little intruder, and that however eager after food they 
might be, they would never willingly touch an Argulus ; 
and that if by chance a fish should swallow one, it would 
almost immediately afterwards be rejected. 
The males are always considerably smaller than the 
females ; and appear, especially in summer, very ardent in 
pursuit of them. They course up and down over the whole 
surface of the fish in search of a mate, and should they 
not succeed in meeting any, they leave their habitation, 
and go elsewhere seeking for one. When they succeed, 
the male mounts upon the female’s back, and carrying his 
body laterally he crosses that of the female, embracing her 
at the same time with his natatory feet. This copulation 
frequently endures for several hours, and during that 
time they adhere so closely, that they cannot be separated 
without considerable difficulty. In the unimpregnated 
female the matrix is very small ; but soon after fecunda- 
tion it begins to increase in size, and in a short time it 
occupies almost the whole cavity of the thorax. The 
number of eggs is very considerable, in the Argulus folia - 
ceus amounting sometimes to 400 ; in the Argulus Cato - 
stomi upwards of 1500 have been seen deposited by one 
female. They carry their eggs for a period between thir- 
teen and nineteen days ; and then, when the female is 
ready to spawn, she detaches herself from the fish, upon 
which she has been living, and seeks a suitable place to 
deposit them. This is either upon a stone or some solid 
body, and as she lays them, she glues them together, so 
that they might be all taken up in a mass. They are laid 
side by side in rows, and are at first of an oval form and 
of a white colour. They soon after become of a dirty 
yellow, and thirty -five days after being laid, the young are 
hatched. In form they resemble a good deal the adult, 
but differ considerably in construction and development 
of their organs. Deceived by this, Muller forms of the 
imperfect young a distinct species, — an error which Jurine 
has pointed out. The shape is oval, or somewhat pyri- 
form, and the eyes and siphon are perfectly formed. 
