Of the two spiders which are shown with their cork nests in Plates VII. and VIII., the purplish grey _Cteniza fodiens_, (Plate VII.) appears to be much rarer than the brown striped _Nemesia cæmentaria_ (VIII.), at any rate at Mentone. I have hitherto only succeeded in obtaining four specimens of the former, though I have searched repeatedly for them at Cannes and Mentone, while the latter species is tolerably common. The nests are, however, often extremely hard to find, and in some cases it is only by chance that I have been able to light upon them. All these trap-door spiders seem usually to prefer rather moist and shady places, and sloping banks or loose terrace walls where the interstices between the stones are filled up with earth, and concealment is afforded by the creeping lycopodium (_Selaginella denticulata_), Ceterach, spleen-wort or maiden-hair ferns, with short moss and splashes of white lichen to distract the eye. It was from such a terrace wall at Mentone, on March 26, 1872, that the nest A in Plate VII. was taken, the tube running obliquely back into the earth between the stones, and the door being concealed by a net-work of lycopodium, one spray of which had been allowed to grow on its upper surface. The tubes of these as of the other kinds of nest are sometimes straight, but more frequently they are bent, and almost always take a downward course. The following is Mr. Pickard-Cambridge's description[60] of _Cteniza fodiens_, the spider which constructs this nest. [Footnote 60: The following description and remarks, printed in a different type, have been kindly prepared for this work by the Rev. O. Pickard-Cambridge, to whom I sent a series of specimens of the spiders preserved in spirit of wine and their nests. My very sincere thanks are due to Mr. Pickard-Cambridge for this assistance, which will give to my publication a value in the eyes of Arachnologists which it could not otherwise have possessed. To all those who wish to study the true structural relations of the four spiders, the habits of which are recorded in the following pages, these details will prove of the highest importance; while those who are only interested in the economy of these creatures can readily pass them over. For observers in the field there is a very ready way of knowing these four spiders apart, as it will be seen that when they are somewhat alike the nests are different (_Nemesia meridionalis_ and _N. Eleanora_), and when the nests are alike (_Cteniza fodiens_ and _Nemesia cæmentaria_) the spiders are markedly dissimilar.] [Illustration: _Plate VI._] FAM. THERAPHOSIDES. Gen. Cteniza, Latr. Cteniza fodiens. Plate VII. Syn. _Mygale fodiens_, Walck. _Ins. Apt._, i. p. 237. _M. Sauvagei_, Ausserer, _Beiträge zur Kenntniss der Arachniden Familie der Territelariæ (Thor.)_, p. 36. Female adult length 10 lines.