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, such as that of _Atypus_, and the funnel nest of _Cyrtauchenius elongatus_, neither of which is furnished with a door. Among the true trap-door nests, those of the cork type stand in a measure alone, being distinguished from all the others by their solid surface doors, composed of many layers of silk and earth; and we do not at present know of any intermediate forms linking the cork and wafer types together. But among the various nests which represent the wafer type the case is different, for here the types naturally fall into a progressive series, such as that represented in the diagrams (Pl. XIV., p. 193). If we try to picture to ourselves the stages through which the most complicated wafer nest--namely, that of the _double-door, branched, cavity_ type (Diagram G 1) may have passed in the course of its development from a simpler ancestral form, we should _à priori_ expect to find precisely such structures as the _Hyères double-door branched_ nest (Diagram F), and the _single-door branched_ nest (Diagram D) forming successive halting-places in the advance from the primitive _single-door, unbranched_ nest (Diagram C). The _double-door unbranched_ type may in like manner find its prototype in the same original single-door unbranched nest (C), which we may look upon as the parent idea, from which all these structures have been derived. Bearing this in mind, and remembering that kinship between living creatures is not only revealed to us by likeness in structure and colour, but also by similarity in habits and instincts, it becomes of interest to trace any resemblance that may exist between these wafer-nests and the dwellings constructed by _Lycosa narbonensis_, a species belonging to the allied family of _Lycosidæ_, and which closely resembles the true _tarantula_[146] of Southern Italy. [Footnote 146: In the United States, and indeed in the New World generally, it seems to be the custom to call all the larger "ground spiders," and especially the trap-door spiders, Tarantulas, but these, in fact, form a distinct group by themselves, belonging to the family _Lycosidæ_.]