. American spiders and their spinning work. A natural history of the orbweaving spiders of the United States, with special regard to their industry and habits. Spiders. Fig. 112. Acrosoma mitrata suspend- ed at the bub of her orb. downward and sustained by the feet, the difference being, as already noted, that the Epeira clasps with her feet the meslied terminations of the radii within the hub, while Acrosoma supports herself by the margin of the open hub. In the case of Rugosa, the method is the same but the position of the spider a little different. The two hindermost legs are clasped to the
. American spiders and their spinning work. A natural history of the orbweaving spiders of the United States, with special regard to their industry and habits. Spiders. Fig. 112. Acrosoma mitrata suspend- ed at the bub of her orb. downward and sustained by the feet, the difference being, as already noted, that the Epeira clasps with her feet the meslied terminations of the radii within the hub, while Acrosoma supports herself by the margin of the open hub. In the case of Rugosa, the method is the same but the position of the spider a little different. The two hindermost legs are clasped to the upper margin or to the bit of ribboned lace that frequently runs upward from the hub of the spiral space. The back or dorsum of her abdomen thus hangs towards the ground. The spinnerets are turned upwards and assist to support the spider by a little dragline. The head in this position is of course depressed, and at an angle say of forty-five degrees, more or less. She supports this part of her body not only by the first and second pair, but Legs contrary to the custom of Orbweavers generally, are thrown forward on either side of the face. Generally the third pair of legs is correlated with the fourth pair, and the second with the first, but here the third is associated with the first two. The fact is doubtless in some way connected with the peculiar character of the fourth legs, which in the genus Acrosoma are as long as or longer than the first legs. The length of the fourth pair is an evident convenience to the spider when walking; for the ventral part of the abdomen is an inverted pyramid or cone, at the apex of which the spinnerets are placed. The ad- ditional length of the fourth legs thus serves to raise these organs above the ground as the spider moves. The same reason, viz., the length of the fourth legs, together with the open hub, influences the position of the third legs. These organs are not long enough to clasp the marginal ring of the hub near the feet of the fou
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectspiders, bookyear1889
