Page:Life-histories of Indian insects - Microlepidoptera - T. Bainbrigge Fletcher.djvu/42

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T. BAINBUIGGE FLETCHER 11 white hairs. There are also capitate smaller hairs on the upper part of each segment.

The larva, about half-grown, was described as "Head yellow. Other segments pale brownish-yellow. A narrow dorsal, latero-dorsal, and spira- eular reddish stripe. Legs pale yellow, prolegs ard claspers dark. Hairs white , except the short clubbed hairs which are black "(^). The full-grown larva " is about 7 mm. long, cylindrical, rather stout, the segmental interstices well marked. Legs and prolegs long and slender ; pale greenish-yellow. Head unicolorous, very pale, trans^parent greenish-yellow ; m.outh-parts darker. Other segments pale greenish-yellow ; a narrow darker green dorsal tne ; each segment with a large but ill-defined, pinkish-red, latero-dorsal spot, the series of these spots forming an interrupted longitudinal line. Two conjoined latero-dorsal tubercles emit a very long white hair directed upwards and a shorter white palmate hair directed upwards and forwards ; a supraspiracular tubercle emits a brown palmate hair directed upwards and forwards ; two conjoined subspiracular tubercles emit a short white hair directed forward and a long white hair directed downward ; there are also one or two latero-ventral tubercles emitting white hairs. The whole surface of the segments is also closely studded with shoit white clubbed secondary hairs "(^).

The larvse feed on the leaves of pumpkin, eating small holes in them and not feeding in from the margin. In the case of pigeon-pea and other pulses, the larva eats into the flower-buds and pods, but never goes fully inside. The clothing of spines and hairs probably serves a protective purpose, since this larva feeds on hairy leaves and pods and is both in colouring and pilosity assimilated to the surface it is on ; it is sluggish in movement and clings tightly where it is openly exposed upon the leaf or pod.

Pupa. Pupation takes place as follows : — The fullgrown larva spins silk upon the leaf or pod over a surface about 10 mm. by 8 mm. and then rests upon this, the anal prolegs firmly fixed in the end of it. The skin splits in front, and slips backwards along the body ; on the underside of the eighth abdominal segment is a distinct bunch of curved hooks (cremastral pad), which engages in the silk as the larva wriggles ; the hind end is then freed from the larval skin and the bunch of stiff recurved hairs on the eighth segment acting as a fixed point, the anal end by WTiggling fixes the tern inal bunch of hooks in the silk. The pupa is thus fastened by two points ; its anterior half is free and can be raised till it is almost at right angles to the fixed abdomen.