If the position assumed (p. 271) on Latreille's own authority, that the true male of N. cæmentaria, Latr., (N. carminans, Latr.), has a bifid point to the prolongation of the palpal bulb, it is clear that the present species is distinct from that of Latreille.
M. Simon describes this palpal bulb as having its extreme point "simple et plus effilée" (i.e. more slender than in the preceding species he has described N. meridionalis). That the examples now before me, agreeing exactly with this description, are not the males of the species above described by myself as N. cæmentaria, Latr., from numerous females found at Montpellier, appears to me clear, not only because I assume that of the true N. cæmentaria, Latr., males will be found to have the point of the palpal bulb bifid, but because the position of the eyes is markedly different in M. Simon's Pyrenean males and the Montpellier females. In the latter the eyes of the front row are separated from each other by equal intervals, in the former the interval between those of the central pair is very perceptibly greater than that between each and the lateral of the same row nearest to it. The interval also between each of the fore-central eyes and the hind-central on its side is proportionally much less.
It appears therefore necessary to characterize N. cæmentaria (Sim. l.c.) by some other name, for if eventually it should be found that Latreille has erred in N. carminans (with the bifid point to the palpal bulb) being the male of his N. cæmentaria, and that the Montpellier species has a male with a simple point to this part, even then the present spider cannot retain its name (cæmentaria), being distinct from the females found at Montpellier.
It is possible, of course, that the present species may hereafter be found, perhaps abundantly, at Montpellier; in that case it will have to be decided which of the two is most likely to be the species described by Latreille. In that eventuality it seems to me that the spider, above described from Montpellier, would be more probably Latreille's species, for one of its specific characters is a tolerably distinct and bold series of, not more than, five dark angular bars along the middle of the upper side of the abdomen, agreeing exactly with Dugès' figures in the Règne Animal of Cuvier, quoted above (p. 271); while in M. Simon's Pyrenean spider, the abdominal pattern of the female described by him, does not agree with this: "il est orné d'une fine ligne noire longitudinale, un peu ondulée, présentant de nombreuses ramifications, s'étendant sur les parties latérales" (l.c. p. 26). The males before me accord with this description, though (as M. Simon also remarks) the "série de fins accents bruns transverses" is "peu visibles et souvent effacés" (l.c., p. 25); in one example this pattern is fairly distinct, in the other it is scarcely recognisable.
The present is a larger spider than N. incerta (the male found by M. Simon at Digne); it is also less distinctly marked both on the cephalothorax and abdomen. The position of the eyes is different, and so also is the palpal bulb; in that species the spine describes a simple curve with a strong outward direction; in the present it is slightly but perceptibly sinuous, and its general direction is parallel to the radial joint of the palpus; the spines also at the upper fore extremity of the radial joint are 5-6 in number instead of three. The outer side of the genual joint of each of the legs of the third pair has three spines; that on the left side, however, of one example, has four. The palpal bulb also appears to be proportionally smaller than that of N. dubia, or of N. Manderstjernæ, Auss. (N. meridionalis, Cambr.)
Another difference may here be noted between the present species and the Montpellier cæmentaria. M. Simon (in lit.) separates his N. cæmentaria from all others by the length of the patella and tibia (genual and tibial joints) of the fourth pair of legs, exceeding in length that of the cephalothorax and falces.
This character has not been found to exist in several females of the Montpellier species, minutely measured by Mr. Moggridge; in them the length of the cephalothorax and falces were found to exceed that of the genual and tibial joints of the fourth pair of legs, by from 11/2 to 2 mm.
In regard to the relative length of the legs of the present species this was 4, 1, 2, 3 in the one example examined, and 4, 1, 2-3 in the other, both being males.
It is a matter of regret that nothing, as yet, has been accurately observed in regard to the particular type or form of the nest of N. dubia.
Habitat. Pyrenees and Spanish mountain regions.