OCR Text |
Show 1902.] SPIDERS OF THE GENUS LATRODECTUS. 251 to Mr. R. Jenery-Shee, an expert in European languages, for kindly looking through Dr. Puga Borne's voluminous work in Spanish, in case I should have missed the paragraph which might have contained the evidence I required. Of the forty-three described species referred to this genus, I am able to recognize six only as distinct, and perhaps eight as subspecies. Of the former, L. hystrix, geometricus, pallidus, tredecim-guttatus, and mactans are probably good species. As to the others, it is very difficult at present to take up any decided position with regard to them, as must always be the case where we have under consideration forms which are actually, at the time of observation, undergoing those processes of differentiation, under the influence of individual variability combined with that of physical surroundings, which, in these early stages, have not yet brought about any definite structural difference, or even any variation in the more superficial characters of colour-pattern, which can be considered in any way constant and exclusive. In the subjoined table will be found the characters by which the most distinct of the species and sub-species of the female sex can best be recognized. The males are not sufficiently well known to enable one to tabulate their characters. Females. A. Integuments clothed with small acanthoid spines and short stiff black spines hystrix Simon. B. Integuments clothed with fine short acanthoid spines and longer bristles, or with fine hairs only. I. Central anterior eyes distinctly larger than the laterals geometricus C. L. Koch. II. Central anterior eyes not larger than the laterals. 1. Integuments almost glabrous. Latero-ventral area clothed with acanthoid spines only. Abdomen entirely creamy-white, with the black impressed muscular scars very conspicuous, and sides slashed with brownish yellow pallidus 0. P. Cambridge. a. Eyes of anterior row, as a rule, equidistant *. a1. Size much larger, length from 12-14 m m . Abdomen either entirely black or brown, without any red spots or with a single square or elongate-oval red spot above the anal tubercle; or with a narrow central dorsal red stripe, broken into two round spots anteriorly, and with, or without, two oblique lateral red stripes. Ventral spot dumbbell-shaped, without a decided dark spot in the middle mactans Fabricius. b\ Size much smaller, length 7 millim. Abdomen rich brown, with three irregular transverse crimson cinctures (very variable in exact form however) and a central posterior crimson band. Ventral spot oblong-oval, with a decided dark spot ^ c curaf.aviensis Miiller. blotch in the middle \ geographicus Hasselt. i Characters drawn from the eye-formula are not reliable ; they vary very much, even amongst examples from the same district. |