460 GEOLOGICAL SURVEY OF THE TERRITORIES. 
nently developed, serving as a rudder organ; after the subsequent 
moults this organ becomes gradually shorter, less movable, bent down, 
loses its bristled margin, and in the females is transformed into two © 
small, scarcely movable, tongue-like bent processes, while in the males 
the same develops itself into disproportionately large claspers with 
broad lobes, functionating as a catching and clasping apparatus. These 
robust claspers, bent downwards and backwards, betray the male sex, 
as above stated, in the earlier stages by an incipient swelling of the said 
rudder organs, while the same, after their hystolytic degeneration, re- 
main small in the females. In this way it was easy for me early to dis- 
tinguish the males from the females and, significant for my experiments, 
to keep them apart. 
The growth and prosperity of the carefully-separated sexes proceeded 
well in various jars with artificial sea water, and pains were also taken 
to add only boiled Utah mud to prevent any Artemia eggs from hatch- 
ing. Without this precaution.I would eventually have received younger 
broods of different sexes together with the older ones, already kept 
apart, which would have interfered with my experiments, in which 
latter the utmost certainty was required to prevent the meeting of the 
two sexes before the setting in of concupiscense. Having raised a large 
number of carefully-watched virgin individuals in the above mentioned 
manner, I waited the period of concupiscence in one-half of their num- 
ber without giving them occasion to come in contact with any males, 
while the other half of virgins I placed together with a number of ma- 
tured male individuals for the purpose of getting fertilized by them. I 
sneceeded in this, since thé males very early, as already stated, betrayed 
their future sex and were vigorously grown up, and gave repeated indi- 
cations of sexual desires. They manifested the latter in their pugna- 
cious behavior, embracing themselves with their powerful claspers in 
such a manner as if they would perform copulation; many of them 
clasped other males, no matter how they struggled against it, and with 
such a violent fervor that they, as may be assumed, applied the claspers 
on almost every part of their body. Such couples remained entangled 
for several days, Swimming around in the most unnatural positions. 
The testicles, filled with whitish zodsperms, presented themselves to 
the naked eye through the translucent body. I selected the most vigor- 
ous individuals, placing them ina jar together with boiled-up Utah mud 
and a number of virgin Artemia, and had then very soon the pleasure 
to see that they did not refuse the ardent embraces of the males, the 
females making no efforts to free themselves of their burden. The 
male with its claspers embraces the postabdomen ‘of the female from 
the back, which region appears swollen by the ovisac. In this way both 
individuals, bearing their abdomens parallel above each other, swim 
about as if animated with but one will. From time to time such a 
couple swims along the surface of the mud, turns around its longitudinal 
axis. dorsal side up, thus whirling up the loose mud for the purpose of 
obtaining food. Occasionally the male, utilizing the embrace of the 
female, bends its postabdomen around for the purpose of inserting its 
two protrusile cylindrical copulative organs into the female genital 
orifice, whereby the closest contact with the female, as well as an afflux 
of spermatic particles, was effected. 
The actual process of copulation, as closely observed by me, was 
interrupted after shorter or longer intervals, but in incessantly long- 
continued embraces it was often repeated. One of these couples hung 
together for three days. After copulation ensued, I transferred those 
females which were abandoned by their males and which females I re- 
