. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. THE WOOLLY WHITE-FLY. 69 The larva, first instar.—Size about mm. by mm.; elliptical, , with 9 pairn of ^^hort marginal bristles, arranged as in iigure 20, the two posterior pairs longest, the relative lengths being as follows: Pair 1 2 3456789 Relative lengths 2 6 4 5 5 4 8 8 After settling, an inconspicuous, transparent, marginal wax fringe develops, but little exceeding in width the length of the marginal .«pines. Eyes reddi.'^h-brown, usual. Dorsimi with 4 pairs of short stout spi
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. THE WOOLLY WHITE-FLY. 69 The larva, first instar.—Size about mm. by mm.; elliptical, , with 9 pairn of ^^hort marginal bristles, arranged as in iigure 20, the two posterior pairs longest, the relative lengths being as follows: Pair 1 2 3456789 Relative lengths 2 6 4 5 5 4 8 8 After settling, an inconspicuous, transparent, marginal wax fringe develops, but little exceeding in width the length of the marginal .«pines. Eyes reddi.'^h-brown, usual. Dorsimi with 4 pairs of short stout spines; 1 pair cephalad and mcsad of eyes, 1 pair at vasiform orifice, and 2 pairs on central region between the fifth and sixth, and sixth and seventh pairs of marginal spines, respectively. Legs and antennae well devel- oped, usual; vasiform orifice similar in shape to that of pupa, but without apparent strong setae. The larva, second instar.—Size, about mm. by mm. All marginal bristles lost except 2 pairs of minute bristles, one at anterior, the other at posterior end of body. Four pairs of bristles on dorsum located as in first instar, but different in that when wax secretions are removed, the first 3 anterior pairs are stout spindle-.'shaped (fig. 21, a), the fourth pair at vasiform orifice, long and slender, as in pupal stage; a fifth dorsal pair at caudal end of body but not on margin, similar to those in pupal stage. Color, brownish or black; margin with narrow white wax fringe, equaling at times mm. Instar conspicuous because of long single, stout, outstanding Avaxen rods secreted by each of the spindle-shaped dorsal spines, and 6 abdominal cross bands of white waxen secretions. Insects well advanced in this instar, after the dorsal waxen rods have developed, pre- sent a profile similar to that showni in figure 21, at b. The larva, third instar.—Size, about mm. by mm. Except in point of size, this re- sembles the pupal instar in all respects
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