226 
DISEASES OE THE COTTON PLANT. 
enabled to transport itself from place to place. The 
antennae, however, are much longer, and the larvae of the 
dragon-fly are decidedly aquatic, instead of living upon the 
land, like those of the ant-lion, 
INSECTS BENEFICIAL TO COTTON. 
Spiders. 
Spiders, in cotton or grain fields, are decidedly bene- 
ficial, inasmuch as they wage perpetual v?ar against other 
insects, and are incessantly on the watch to catch and 
destroy all which, in their erratic flights, happen to be- 
come entangled in their webs. 
One spider makes a very singular nest for her young, 
of fine silk, webbed up and closely woven together in the 
shape of a basket with a round bottom, and most generally 
placed on or near the top of the cotton plant, Tliis basket 
is furnished with a cover fitting closely to the top, and is 
filled with egg-s. When the young spiders are hatched, 
they creep from under this cover, and eventually disperse 
over the web, which is comparatively large and strong, and 
stretched from plant to plant. The old female spider 
appears to brood over this nest, displaying much maternal 
solicitude for the safety of her infant progeny ; for, if forced 
away, she immediately returns, and will sufter herself al- 
most to be torn limb from limb, rath.er than desert her 
precious charge. 
The habits of the different species of spiders are very 
dissimilar ; for, while some are almost entirely stationary 
all their life-time, others are continually moving about, 
roaming from leaf to leaf, and living entirely by hunting. 
Many spin their nets from plant to plant, to entrap unwary 
insects, and generally stay quietly at home in comfortable 
