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her prey, and to escape from the least danger. Degeer has 
seen her with her head upwards, and the feet applied against 
the body. 
It is easy to conceive the mode in which the argyroneta 
introduces the air into her ball, and how she totally fills it. 
At first the water may be supposed to occupy its interior 
capacity. To empty it, and substitute another fluid, the animal 
goes continually to the surface of the water, charges itself 
with a bubble of air, transports it into its habitation, un- 
burthens itself of its aerial provision, and displaces an equal 
mass of water, which issues through the lower aperture. By 
repeating this operation several times, it succeeds in expelling 
all the water out of its cell, and introducing the same volume 
of air. The males, as well as the females, construct for 
themselves, at all the favourable seasons of the year, similar 
habitations, which demonstrates the analogy existing between 
these and the other araneides of the same tribe. Degeer 
found, in the month of December, one of these balls, closed 
in all parts, and in which the animal was, as it were, im- 
prisoned. It issued forth through a rent made by this ob- 
server, and immediately proceeded to suck a fresh-water 
assellus, which he presented to it. It is probable that these 
aranekles shut themselves up in this manner to pass the winter. 
The same naturalist, as well as Clerk, has preserved, in the 
same vessel, many individuals of both sexes, without one 
devouring the other ; and though they had been deprived, for 
several days, of every kind of nourishment, all that passed in 
the rencontres between male and male, and female and 
female, was simply touching each other, or attacks which led 
to no murderous conclusion. Thus some writers have falsely 
attributed to the aquatic spiders, probably presuming from 
analogy, a cruel and voracious character, with regard to their 
own species. 
The eggs are round, of a yellow sulphur colour, and shut up 
