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Show 1900.] MR. R. NEWSTEAD O N A N E W SCALE-INSECT. 947 7. O n a new Scale-Insect from Zomba, British Central Africa. By R. N E W S T E A D , F.E.S., Hon. M e m . R.H.S. [Received September 28, 1900.] (Plate LIX.) WALKERIANA PERTLNAX, n. sp. 2 • Adult (PI.LIX. figs. 1,2,3) dark castaneous, slightly shining; form above generally highly convex and evenly rounded, forming an almost complete hemisphere, but one specimen was decidedly more elongate and less convex ; cephalic area suddenly constricted, much wrinkled and furrowed at the sides, and with 4-6 large, deep, and variously-shaped punctures; margin in front emarginate, and within a broad, deep, upwrard-sloping, central groove, surmounted on either side by a strongly-rounded ridge. Subdorsal and marginal rows of very short, stout, dusky-white, waxy processes, placed close together, and gradually lessening in size from the centre towards the extremities; there is also a double dorsal row of much smaller processes, which also lessen towards the extremities, the largest pair occupying almost a central position. Much mealy substance is scattered round the base of the waxy processes, and the hollows and wrinkles are covered with the same material. Underside (fig. 3) flat or slightly concave, with radiating grooves, more or less covered with white mealy secretion; sides sharply raised. Antennae (fig. 5, 5 a) of 10 joints, of which the terminal one is much the longest, and, with the exception of the first, all the joints are furnished with short, fine hairs : formula 10,1, 2, 3 (4, 5, 6) (7, 8, 9). Legs (fig. 4, b) very small; digitules to claw simple. Eostral apparatus present, but owing to the density of the surrounding tissues it is impossible to make out its true character. Ventral opening (fig. 4) very large, somewhat hexagonal and without marginal hairs, the whole aperture covered by a thin anteriorly-binged valve or flap (fig. 3) of dark brown secretionary matter occupying approximately the area indicated by the dotted line in fig. 4; the line of attachment being immediately beneath the insertion of the posterior legs, its exact course being indicated by large gland-tracks (fig. 4, a, a), the largest of which are hidden beneath the legs. Epidermis covered with minute hairs and circular glands. Long 14-20*50, wide 11-15, high 7-10 mm. Larva (figs. 6, 7) elongate ovate, above (fig. 6) with median, subdorsal, and marginal bands of spiny hairs. Antennae (figs. 8, 8 a) of 5 joints, of which 5 is equal in length to 2, 3, and 4 together: formula 5, 3, 2, 1, 4. Legs very long and slender; digitules to claw very fine simple hairs ; claws (fig. 9) faintly tridentate. Anal ring without hairs. PROC. ZOOL. Soc-1900, No. LXII. 62 |