Nests of the double-door unbranched type.
Nemesia Eleanora, Mentone, and Cannes.
As far, therefore, as I know at present, the cork type of nest is the only one which is widely spread, and which is constructed by spiders of more than one species. For, while the single-door wafer, and the branched and unbranched double-door nests are each the work of one particular spider, we see that nests of the cork type are made by spiders of six distinct species, belonging to at least three genera.
It is almost certain that a much larger number of spiders of different kinds, though all probably members of the sub-order Territelariæ, construct nests of the cork type, for descriptions and specimens of trap-doors of this kind are brought from the most distant parts of the globe. It is true that these specimens and descriptions usually only show us the surface-door, but as far as our present knowledge goes, we are led to suppose that a door of the cork type is always associated with a simple tube, in which there is no trace of a second door or valve, so that, judging of the unknown by the known, we conclude that nests which possess the characteristic peculiarity of a true cork door are true cork nests in other respects also. Further research may possibly show that there are exceptions to this generalization, but I do not at present know of any.
I have seen Australian specimens of large trap-doors, of the cork type, measuring from one to two inches across. In some of these the doors were scarcely more than semicircular but very thick, and having their edges bevelled so as to correspond with the sloping margin of the tube;[92] in others, found at Paramatta, and described to me by Lady Parker as being tenanted by a black spider, the doors were said to be circular and much smaller, scarcely larger than a sixpence, and of the cork type.
[92] Specimens of Australian nests may be seen in the cases at the British Museum.
The upper portion of a nest from New Granada has been figured and described by M. Victor Audouin,[93] which closely resembles that drawn at Fig. A in [Plate VII.], p. 88, but the door is about a third larger.
[93] Note sur la demeure d'une araignée maçonne de l'Amérique du Sud. Annales des Sciences Naturelles (Zoologie), tom. vii. tab. 3, p. 227-231.
I have also been assured that nests of the cork type are found in many parts of India, and we have seen above that they are reported to be common in the island of Formosa.
Putting all this together, it will be seen that nests of this type are found all round the globe; in Formosa, India, Syria, the Grecian Archipelago, Italy, and the adjacent islands, Trieste, South France, Spain, Morocco, New Granada, and Australia; while the single-door wafer nest is only known at present in the West India islands;[94] the branched double-door nest at Mentone, Cannes, and Pegli near Genoa, and [doubtfully] near Naples and in Ischia; and the unbranched double-door type at Mentone and Cannes alone. It is quite probable that these three latter forms of nest will some day be found to have a much wider range than that assigned to them here, but I can scarcely think it likely that they will ever be shown to claim the world-wide distribution of the cork type. Supposing that these nests are eventually discovered in many widely distant localities, a very interesting question will arise as to the specific characters of the spiders which inhabit and construct them. Shall we then find, for example, that nests of the unbranched double-door type are not tenanted and fabricated by Nemesia Eleanora alone, as we have hitherto found to be the case, but by many other distinct species also, each in its peculiar district?