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Show 430 MR. H. R. HOGG ON AUSTRALASIAN SPIDERS. [Dec. 2, appear to have been developed in Australia proper, and few of its members have strayed away thereform. The whole of its species have the male palpal spiral in its most fully developed form with about 10 spirals. The cephalothorax is set on straight with the body; in altitude it is generally less than any member of the preceding genera, and in profile varies from a continuous curve highest about the middle to a flat surface. The latter form comprises two, or perhaps three, species hitherto known as Holconia (Voconia) Thor., but which, except for the flatter cephalothorax and consequently lower clypeus, differ in no particular from the rest of the Isopedce. Thorell himself was doubtful how to place his northern form, II. subdola Thor. ; and in the only specimens I have seen to attribute to H. dolosa L. Koch, the cephalothorax is quite as normally rounded as many other species of Isopeda. In a few instances the eyes of the front row, which is straight or slightly procurved, are all equal, but more generally the laterals exceed the median in diameter in the proportion of about 5 to 4. The rear row is also straight or slightly procurved, about a third longer than the front row, the rear median eyes always smaller than any of the others, and either rather nearer together than they are from the lateral, or equidistant. The median eye-square is broader than long. The cephalothorax is as broad as or broader than long and straight in front, where it is generally about two-thirds the greatest width. The legs always in the proportion 2 14 3. N ote.- The name Isopeda L. Koch has given rise to some discussion at various times in consequence of its being certainly wrongly formed from the Greek. Thorell and Simon set it down to a lapsus calami and boldly write Isopoda, but L. Koch uses his original form a score of times (and never any other) within a few pages of Heteropoda, also used by him over and over again. It certainly was no lapsus calami but deliberately intended. He probably knowingly spelt it wrongly to avoid clashing with the order of Crustacea Isopoda. The name is altogether a misnomer as applied to this genus, for no two pairs of legs of any of the species are alike in length. The only species which had two pairs of legs (i. and ii.) of equal length has been removed to a new genus (Pediana E. Sim.), though for other reasons. Synopsis of Genus Isopeda L. Koch, Females. A. Sternum deep jet-black. A 1. Underside of abdomen whole-coloured, without any transverse dark stripe behind the genital fold. a1. Eyes of front row equidistant. a2. Distinguishable markings on back of abdomen. a3. Three pairs of dark spots on whole-coloured back of abdomen; coarse hair on abdomen, rather coarse on cephalothorax; cephalo-tliorax longer than tibia i ................................... frenchi, nov. sp. |