FIG. 48.--_A._ Scheme of under surface of Wolf Spider (female). _B._ Pedipalp of male (enlarged). For other references, see text.] The Common Garden Spider (_Epei´ra diade´ma_) is a very good subject, and there can be no difficulty in procuring any number of specimens. The smallest garden will be sure to yield a plentiful supply; and even if we have no garden, a very superficial search among the hedgerows will give us as many as we can possibly want. Every one knows this spider, and the beautifully regular web which it makes. First of all, what one may call the outline of the web is spun--strong threads stretching from point to point, to which are attached lines radiating from a common centre. This may be represented diagrammatically by drawing a circle and producing radii from the centre to the circumference in all directions, or by making a rectangular figure and drawing lines to the boundaries from the point where the diagonals intersect. It must not, however, be supposed that the outline of the web is of a regular form. In this respect the spider adapts itself to circumstances, and spins a greater or less number of supporting threads, as may be necessary. [Illustration: FIG. 49.--Garden Spider and Web.] Then the spiral is made (Fig. 49) from the centre to the circumference. The first few turns are of the same character as the radial lines; but all the rest of the short lines forming the spiral, and connecting the radial lines, are coated with a viscid secretion, which is the essential part of the snare; for the victims are really limed like birds on a twig, not entangled in the threads. It is well to test the character of the different parts of the spiral, not only by touch, which is convincing enough, but with pocket lens. Our low powers will not give such results as are shown in Fig. 50, but we shall have no difficulty in distinguishing the sticky parts from those not coated with the secretion. [Illustration: FIG. 50.--_A_ Adhesive Threads of Spiral. _B._ Non-adhesive Radial Threads.]