242 THE HARMONIES OF NATURE. 



usually selects still waters. Her house is an oval cocoon lined 

 with silk, from which threads issue in every direction, and are 

 fastened to the surrounding plants ; in this cocoon, which is 

 open below, she watches for her prey, and even appears to pass 

 the winter, when she closes the opening. It is most commonly 

 entirely under water, but its inhabitant has filled it with the 

 air needful for respiration, and breathes as easily in her sub- 

 aquatic home as if her wonderful nest were suspended in the 

 atmosphere. The manner in which she fills her cell is very 

 curious. She ascends to the surface slowly, assisted by a thread 

 attached to the leaf or other support below. As soon as she 

 comes near the surface, she turns with the extremity of the 

 abdomen upwards, and exposes a portion of the body to the air 

 for an instant; then, with a jerk, she snatches as it were a bubble 

 of air, which is not only attached to the hairs which cover the 

 abdomen, but is held on by the two hinder legs, which are 

 crossed at an acute angle near their extremity this crossing of 

 the legs taking place the instant the bubble is seized. The 

 little creature then descends more rapidly and regains her cell, 

 always by the same route, turns the abdomen within it, and 

 disengages the bubble. In this way more than a dozen journeys 

 are performed sometimes two or three very quickly one 

 after another, at other times with a considerable interval 

 between them, during which period the industrious little animal 

 is employed in extending and giving shape to her silvery dome, 

 getting into it, pushing it out at one place, and amending it at 

 another, and strengthening its attachments to the supports. At 

 length, when satisfied with her work, she settles in her den 

 head downwards, and, undisturbed by the wind that ruffles the 

 surface of the pond, lies in wait for her prey, or, having dragged 

 it to her cavern, leisurely devours it. 



She also places her eggs in this cell, spinning a saucer-shaped 

 cocoon, and fixing it against the inner side and near the top. 

 In this cocoon are about a hundred eggs, of a spherical shape, 

 and very small. The cell is a true home for the young spiders, 

 who, when sufficiently strong to provide for themselves, are 

 turned adrift by the mother, and, prompted by their wonderful 

 instinct, soon construct a subaquatic home similar to that in 

 which they first drew breath. 



The raft-spider is another aquatic or rather semi-aquatic 



