In enlarging the images of these small spiders to many times their size, one is at once struck by their similarity to crabs and lobsters. Their jointed legs encased in shells, which from time to time they shed, remind one strongly of the crabs, and they do in fact belong to the some great family, the family of arthropods, and they are not insects. The spider world is the world of eight-legged creatures just as the insect world is the world of the six-legged ones, and educated men and women should no more confuse these great classes of beings than they confuse the bipeds with the quadrupeds. They differ from the insects in other ways than in the number of their legs--they have no feelers or antennæ, those wonderful sense organs which all insects have, but here and there, especially on the legs, are strange hollow bristles or spines, which end in nerves. Their eyes also are not like insects' eyes. An insect's eyes, at least its large prominent ones, are composed of hundreds of lenses or facets, while the spider, though he generally boasts of eight, has only simple ones with single lenses. Their life is very simple as compared with that of many of the insects. In the fall, the mother spiders lay their eggs in a bag of their own silk, often several hundred eggs being laid in one sac. The spiderlings hatch out in the sac, and, in the North, they spend the long winter there. They do not have two stages of existence as beetles or butterflies do, but are hatched out mature and equipped with the poison fangs which aid them in their strictly carnivorous, and often even cannibalistic, existence. They grow and shed their skins as do the baby grasshoppers, but they do not change their form with each moult and none of them have wings. They have inside their bodies, reservoirs of strange, sticky fluids which they can pour out through spigots in many different ways. This fluid, as it dries, may form drag lines which they trail behind them and fasten as they go to use for safety lines; with some spiders it may even be poured out in such quantities that it makes an aeroplane; with the majority, however, it is used to make their nests or their egg sacs or the marvelously beautiful orbs that prove the graveyards of so many careless insects. For the spiders are the enemies of the insect world; were they more discriminating, they would be perhaps the greatest friends of the human race, but, as they suck all kinds of insects' blood, all that we can be sure of is that those among them which we find in our houses are a benefit, for there they kill the flies and other insects which we do not want indoors.