Page:Supplement to harvesting ants and trap-door spiders (IA supplementtoharv00mogg).pdf/103

 defences which they employed when they had families to protect.

Since my attention was drawn to the existence of this cavity in the dwellings of N. Manderstjernæ I have never noted the presence of young in those nests in which the cavity was filled up and disused; but then I have only exact records with reference to this point in the case of seven nests.

In these seven nests, however, there was no free cavity, and there were no young spiders, though it was at the season when it was common to find young in the nests.

The question, therefore, remains open, and further observations on this head would be very acceptable. I detected the débris of insects, and especially the horny coats of ants, in the descending cavity, in many nests; and in some of the oldest, where it had become completely blocked up, these remains still indicated its former outlines and position.

The nests of N. Manderstjernæ at Cannes correspond both in respect of the cavity and of their other characteristics with those at Mentone. N. Manderstjernæ occurs pretty abundantly at San Remo in the olive-grounds east of the Sanctuary, but I can say nothing as to whether the nests there possessed the cavity or not, for, when I was there, I was not aware of its existence. I obtained a single example of N. Manderstjernæ and its nest at Hyères, and this is the westernmost point at which this species has as yet been detected.

We have now passed in review all the seven known types of true trap-door nest, and have taken note also of the lower and more rudimentary forms of nest,