The egg-sacs of the cobweb weavers can be found suspended in their webs; and those of the orb weavers, in various situations. Fig. 108 represents the large egg-sac of one of the orb weavers. This is made in the autumn, and contains at that season a large number of eggs--five hundred or more. These eggs hatch early in the winter; but no spiders emerge from the egg-sac until the following spring. If egg-sacs of this kind be opened at different times during the winter, the spiders will be found to increase in size but diminish in numbers as the season advances. In fact, a strange tragedy goes on within these egg-sacs: the stronger spiders calmly devour their weaker brothers, and in the spring those that survive emerge sufficiently nourished to fight their battles in the outside world. [Illustration: _Fig. 108. Egg-sac of an orb weaver._] The females of the _Running Spiders_ not only make a carefully constructed egg-sac, but also care for the young spiders for a time. The running spiders are the large dark-colored, hairy spiders, often found under stones and rubbish; they are so-called because they capture their prey by running. The females of most of the species (those of the genus _Lycosa_) drag after them their egg-sac, which is attached to the spinnerets (Fig. 109); and when the young hatch, they climb on their mother's back, and are carried about for a time. [Illustration: _Fig. 109. Lycosa and egg-sac._] One of the running spiders (_Dolomedes_) carries her egg-sac with her mandibles until the young are ready to emerge. At this time the mother fastens the egg-sac in a bush, and spins irregular threads about it, among which the young spiders remain for a time (Fig. 110). In the specimen figured, the egg-sac was concealed in the upper part of the web. THE BALLOONING SPIDERS. In warm autumn days, innumerable threads can be seen streaming from fences, bushes, and the tips of stalks of grass, or floating through the air. These are made by the _Ballooning Spiders_, which are able to travel long distances, hundreds of miles, through the air by means of these silken threads. The ballooning spider climbs to some elevated point, and then, standing on the tips of its feet, lifts its body as high as it can, and spins out a thread of silk. This thread is carried up and away by a current of air. When the thread is long enough the force of the air current on it is sufficient to bear the spider up. It then lets go its hold with its feet and sails away. That these spiders travel long distances in this manner has been shown by the fact that they have been seen floating through the air at sea far from land. [Illustration: _Fig. 110. Nursery of Dolomedes. _] LEAFLET XVI. LIFE HISTORY OF THE TOAD.[20] BY S. H. GAGE.[21] [20] Teachers' Leaflet, No. 9, May, 1897.