Page:Supplement to harvesting ants and trap-door spiders (IA supplementtoharv00mogg).pdf/117

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attempt to drag a house-fly entire down their tubes for which it is much too large, when the door is pushed open, and the fly remains sticking in the entrance to the nest with its legs up in the air. One may even feed these spiders oneself by approaching carefully and, without causing any vibration, pushing the fly, placed on the end of a pencil, within reach of the spider.

I have given my reasons before (Ants and Spiders, p. 127) for believing that the trap-door spiders do not as a rule desert their nests, but enlarge them from time to time to meet their own requirements of growth; showing, by a comparison of the measurements of the doors of eight nests in April with those of the same nests in the following October, that all had increased in size.

Subsequent observations have confirmed this; I find that the young spiders taken from the mother's nest enlarge their nests in captivity in a precisely similar way.

Thus, for example, the wafer doors of three young Eleanora spiders, made within a few days after their removal from the mother's nest on February 20th, 1873, and first measured on February 28th, had increased between that date and Nov. 29th following from 2 to 4 lines, 2-1/2 to 4 lines, and 2-1/2 to 6 lines respectively.

It is unfortunate that the male and female spiders are undistinguishable when very young, as it would be interesting to know whether the males construct nests before they take to their adult life, during which they roam from place to place and hide under stones.

In one case fourteen young spiders, forming this entire family taken with a female N. Manderstjernæ,