Page:Supplement to harvesting ants and trap-door spiders (IA supplementtoharv00mogg).pdf/97

 Auss. (formerly called N. meridionalis), has already been partially made known by the figures and description given of it in Ants and Spiders (Plates IX., X., and XI., pp. 98, 100, and 104); but I have to confess, with great regret, that when these illustrations and descriptions were published, I was not fully acquainted with the true structure of this nest, having overlooked the existence of a short descending cavity which leaves the main tube a little above and on the opposite side to the ascending branch. This cavity is always present, but the very largest and oldest spiders usually allow it to become filled up with remains of food and particles of earth, and sometimes even spin silk across its entrance, in which case it can only be traced on very close examination.

It was from an old nest such as this, in which the descending cavity had been closed up, that the large drawing at fig. A on Plate IX. of ''Ants and Spiders'' was made, and this figure, therefore, still remains substantially correct.

But in the case of the other illustrations—namely, fig. B, Plate IX., fig. A, Plate X., and figs. B and B 1, Plate XI., where nests of young spiders, or of spiders