. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. TECHNICAL DESCRIPTION OF STAGES. 119 the second, the two following are subequal and shorter than the first, the fifth is shorter than the fourth, and the sixth and seventh are subec^ual and shorter than the fifth, tlie last tapering regularly from the apex, which is armed with curved spines, one long and one short. The terminal three joints form something of a club tip. During this stage the larva increases in length to more than 3 mm. and the abdo- men swells and becomes more robust. The length of the hard chiti
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. TECHNICAL DESCRIPTION OF STAGES. 119 the second, the two following are subequal and shorter than the first, the fifth is shorter than the fourth, and the sixth and seventh are subec^ual and shorter than the fifth, tlie last tapering regularly from the apex, which is armed with curved spines, one long and one short. The terminal three joints form something of a club tip. During this stage the larva increases in length to more than 3 mm. and the abdo- men swells and becomes more robust. The length of the hard chiti- nous parts remain, however, unchanged, as follows: Anterior femora, mm.; anterior tibitie, mm.; hind tibiae, mm. This stage lasts more than a year, the first molt usually occurring during the second year after hatching. (See fig. 47.) Second larval stage.—The average length of the larva in this stage is about 4 mm. The more horny parts now measure: iVnterior femora, mm.; anterior tibiae, mm.; hind tibige, mm. The general appearance is unchanged from the later development in the preceding stage. The eye-spots are still present, though reduced. The under surface of the head is armed with some rather long hairs, and a very regulaj' row of minute spines occurs on the anterior face of the hind and the middle femora. The prominent apical tibial spur of the middle and the hind pair ap- pears with this molt, being previ- ously represented, if at all, by a sim- ple spine. The third joint of the now distinctly elbow^ed antennae is Fig. 48.—second laival stage: a, anterior leg, , . 1 ' 1 1,1,1 outer face; 6, same, inner face. (Author's as long as the second, and the three illustration.) terminal joints are rather more coin- pressed into a club-like tip than in the first stage. The chief charac- teristics of this second stage, however, are in the anterior legs (fig. 48). The femora now possess a rudimentary comb of three teeth, the upper tooth being very
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