DIAPTOMUS. 
225 
place, a body like one of these tubes may always be seen 
concealed in the sexual parts ; but immediately after 
copulation has taken place, nothing of the kind can be 
observed in a state of development. Jurine, as I have 
observed above, had occasionally seen them in the male, 
attached to the base of the posterior feet ; and Siebold 
states, that once, upon separating a pair in the act of 
copulation, he found a seminal tube attached to the end 
of the last pair of feet of the male, “ apparently,” he says, 
“ before he had had time to rid himself of the body.” 
It has been observed, that the males of this species are 
very lustful, and they have been seen to attack in succes- 
sion several females, some of them even such as had had 
connection immediately previous with other males, or that 
had external ovaries suspended from their abdomen, so 
that it is not uncommon to find two, three, four, and even 
five of these tubes in the same female. These tubes are 
all similar in size, form, and contents. They are straight, 
and scarce extend in length beyond the point of the tail. 
They are composed of a colourless, solid envelope, which 
is rounded at its inferior free extremity, and terminates at 
its upper end in a short, narrow neck, provided with an 
opening. Each tube contains three different kinds of 
matter : one is white and thick, of a glutinous nature, ex- 
tending the whole length of the tube, and is coagulable in 
water ; the second consists of a great number of very small, 
oval, well-formed bodies, which Siebold considers the real 
zoosperms of the animal; while the third is composed of 
a mass of oval bodies of a similar size, and composed of 
very fine granules. This latter granular portion of matter 
occupies the inferior half of the capsule ; the second portion 
lies in the upper half, while the neck only is filled with the 
first kind, or the glutinous substance. As soon as the 
tube quits the sexual organ of the male, the relative situa- 
tion of these substances changes. Immediately it comes 
in contact with the water, the third or granular mass 
swells, the little oval, granular bodies become round, swell 
more and more, till at last they expel the first or glutinous 
15 
