OCR Text |
Show 1880.] OF T H E GENUS ARG\RODES. 329 of a dark yellow-brown colour. The palpal organs are tolerably complex, but compact, and, like those of most others of the genus, devoid of any very remarkable process. The falces, maxillce, labium, and sternum are of normal form and structure, and similar in colour to the cephalothorax. The abdomen has its hinder extremity produced in an oblong-form, the apex being a little dilated but slightly bifid, becoming somewhat of a fish-tail form; the length from the fore extremity to the spinners is a little less than that from the spinners to the apex. The colour of the abdomen is brownish black, marked, mottled, and speckled with pale yellowish-white and silvery spots and markings. The most conspicuous of the latter form two longitudinal slightly curved lines or bars along the fore part of the upperside, enclosing an oblong or somewhat coffin-shaped black-brown marking; also on the hinder part of each side, a little above the spinners, is a somewhat V-shaped marking formed in a similar way. Two adult males of this very distinct Spider were contained in the small Madagascar collection received from Mr. R. H. Meade several years ago. ARGYRODES FISSIFRONS. (Plate XXIX. fig, 8 a'.) Argyrodes fissifrons, Cambr. Linn. Soc. Journ. Zool. x. p. 380, pl. xii. figs. 31-38 ; T. Thorell, Ann. Mus. Genov. xiii. p. 145 (1878). Argyrodes inguinalis, T. Thorell, /. c, p. 149. This Spider is nearly allied to the next Spider described, Argyrodes procrastinans(Plate XXIX. fig. 9); but the latter is, I feel no doubt, a distinct species, the form and markings of the abdomen (fig. 9, a) being different from many examples of the female of A. fissifrons received from Ceylon. I have, however, considerable doubt whether^, inguinalis, Thor., is distinct from A. fissifrons. Dr. Thorell (I. ci) says that, excepting in the genital process, he can find no reliable difference between the two species (the female only of A. inguinalis being known to him). The genital process is in almost all Spiders a point of structure of the first importance for the distinction of species; but with respect to Argyrodes I have not found it so reliable, as it is subject to great differences in external appearance, owing to the adventitious addition of the resinous-looking accretion mentioned above (p. 320). I am the more inclined to doubt the distinctness of Dr. Thorell's A. inguinalis-, inasmuch as in an example he has kindly given me of it I observe traces of this accretion; and, excepting for this, there is no difference at all from my Ceylon examples of A. fissifrons. In one of the latter there is a similar disfigurement, which renders it quite undistinguishable from A. inguinalis. Of the identity of Dr. Thorell's types (from Amboina) of A. fissifrons, and those I have received from Ceylon there is no doubt. The figure given (Plate XXIX. fig. 8 a') is from one of several ex-amples& kindly sent to me by Dr. Thorell. In the form of the apex of the abdomen the females differ considerably, some examples being drawn out into a much longer and more acute point than |