Page:Popular Science Monthly Volume 62.djvu/158

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POPULAR SCIENCE MONTHLY.

burrows, which sometimes end in a hole or a cup-like depression in the ground and are beautifully lined with soft, white silk. Very large spiders are nearly always under large heavy stones; one might almost say that the size of the stone varies as the size of the spider. They prefer the stones on the flats or rands or the boulders at the foot of the kopjes. Occasionally they sink a hole an inch and a half in diameter in the open karoo soil and spin strands of web across its mouth. In one such hole I dug up an adult female with her numerous young, and it was a curious sight to see the young swarming over the great spider. The hole dropped perpendicularly for about six inches and ran at right angles for another foot. The lairs of these spiders are always strewn with bodies of beetles, large and small, eloquent evidences of the sad tragedies that are enacted in insect life. The new Harpactira is common at Hanover, though one does not often find really fine examples of adults. The adult males are rarer than the females, from which they may be distinguished by their slighter bodies and longer legs and by a peculiar pear-shaped spine at the ends of the palps.

We now come to the regular trap-door spiders, the Ctenizidæ, that sink a cylindrical silk-lined tube into the earth and affix a hinged lid to the opening. Of these I have found seven species, all of them, I believe, new. Perhaps the greatest interest gathers round a new Hermachastes. At Cape Town, the representative of this genus has hitherto invariably been found by Dr. Purcell with a trap-door to its hole, but the Hanover species has made a new departure. I have dug up over a hundred, I should think, and have never yet found one with a door. Some have escape blind side chambers, but I have been unable to find a door, either inside or outside. On the contrary, they have the uniform habit of building up a tube with irregular rim, projecting above the ground and varying in height from being just perceptible to a perpendicular regularly cylindrical funnel about an inch and a half high, the average height being more than half an inch. These projecting tubes are built of leaves, pieces of grass or small sticks, and are bound together and lined inside with white web, which extends throughout the length of the underground hole. This habit, as far as regular trap-door spiders are concerned, was, up to this discovery, quite unknown in South Africa; though I believe there are trap-door spiders in northern Africa which apparently build a similar projecting tube. I have not yet found the adult male of this Hermachastes, which probably lives under stones by day—a habit common to the males of this family; but the making of the nest as described has been established with regard to adult females, males up to the last molt, and the young of both sexes.