Page:Supplement to harvesting ants and trap-door spiders (IA supplementtoharv00mogg).pdf/96

 the knife (a common table-knife), which furnished me at once with a good specimen of the nest and of its occupant.

When the spider has once fairly determined upon resistance, it is scarcely possible to make her retreat without destroying the nest, and, in one case, when I tried to push the lower door down from above, while she was pressing it upwards from below, I found that, without crushing my opponent, I could not succeed.

There were probably young in the nest on this occasion, for I have frequently found them in the nests with the mother at this season. In no case did I even catch a glimpse of the male, and this sex is at present unknown.

The young spiders make their nests at an early age, and there can be no doubt that N. congener enlarges its dwelling from time to time as growth demands, just as the trap-door spiders at Mentone do. Indeed in one of these new Hyères nests I found, outside the main tube and some way above the existing lower door, a former and disused lower door much smaller than the one then in use, and which had evidently belonged to the nest at a previous stage of its development. I have observed this before in the nests both of N. Manderstjernæ and N. Eleanora.

This new type is strictly intermediate between the double-door unbranched wafer nest constructed by N. Eleanora, and the double-door branched wafer with the descending cavity which I am now about to describe.

This latter nest, the work of N. Manderstjernæ,