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Torquenado Directory 05
Page 02
Spiders, which do not undergo such changes as do most of the common, six-footed insects, winter either as eggs or in the mature form. The members of the "sedentary" or web-spinning group, as a rule, form nests in late autumn, in each of which are deposited from fifty to eighty eggs, which survive the winter and hatch in the spring, as soon as the food supply of gnats, flies, and mosquitoes appear. The different forms of spiders' nests are very interesting objects of study. Some are those close-spun, flat, button-shaped objects, about half an inch in diameter, which are so common in winter on the under side of bark, chunks and flat rocks. Others are balloon-shaped and attached to weeds. Within the latter the young spiders often hatch in early winter, make their first meal off their empty egg cases, and then begin a struggle for existence, the stronger preying upon the weaker until the south winds blow again, when they emerge and scatter far and wide in search of more nutritious sustenance.
Once started in the launch _Rimac_, we went through interesting channels, outlets of the main stream being often noticeable on either bank, cutting wide passages through the forest and forming one or more shallow lakelets, with innumerable aquatic plants on the surface of the water. As we went farther it became easy to understand how islands were constantly forming in the river. Quantities of large and small logs of wood were continually floating down the stream; the banks were gradually being eaten away by the current. Whole trees fell down with their immense branches and polypi-like roots, and formed a barrier arresting the progress of the floating wood. Particles of earth deposited by wind and by water saturated with impurities settled there. Soon grass would begin to grow on those deposits, which quickly collected more deposits of flying and floating particles. The soft bottom of the river, disturbed by the deviated current, piled up mud against the submerged branches resting on the river-bed. Quickly an island was then formed; more wood accumulated, more grass, more mud; the base of the islands would increase rapidly, and in the space of a few years islands several kilometres in length rose above the water.
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