CYPRESS BARK SCALE. 9 



A, 2) six-segmented, first segment broadest, sixth longest. Normal antennal 

 formula as follows: 6, 1, (2, 4, 3, 5). Joints 2, 3, 4, 5 subequal and variable, 

 thus causing various formulae. Antennae rather hairy. Fifth segment bearing 

 one broad spine, while four occur on sixth segment. Eyes marginal, set a 

 short distance behind antenna?. Legs rather short and stout. Tarsus slightly 

 longer than tibia, the two combined slightly longer than femur and trochanter 

 combined. Legs rather hairy, tarsi bearing four knobbed digitules. Usual 

 coccid sucking mouthparts present. About 26 trilocular pores set rather 

 regularly about margin and two longitudinal rows of the same type on dorsum 

 of insect. Caudal seta? (PI. V. B, 1) prominent, rather stout, and about 140 fi 

 long; borne on small inconspicuous anal lobes. Anal ring bearing six seta?, 

 noticeably longer than in later stages. A number of short spines scattered over 

 body. 



SECOND IN STAR. 



Immediately after the first molt some differences between the sexes can be 

 detected under the microscope. Toward the end of the second stage an ex- 

 ternal difference can be observed in the shape, the female being broader than 

 the male. 



Female larva (PI. IV, C) about 0.84 mm. long and 0.51 mm. wide, oval in out- 

 line, yellowish brown in color. Legs and eyes similar to those of first-stage 

 larva. Antenna? very similar except that sixth segment bears only two broad 

 spines. Caudal seta? (PI. V, B, 3) much shorter, being only 37 /x long. Anal ring 

 still bearing six hairs, also shorter than in preceding stage. A larger number 

 of tubular wax ducts, varying from 40 to 75, to be found on dorsum, particularly 

 abdomen, and on lateral margin. Also a number of trilocular pores and small 

 spines scattered over body. 



M ale larva (PI. VI, A) about the same length but narrower than female; 0.85 

 mm. long by 0.43 mm. wide. Color yellowish. Caudal seta? twice as long as 

 those of female, half as long as those of first-instar larva, 75/*. Six anal hairs, 

 in length equaling diameter of anal ring; longer than those of second-stage 

 female, but shorter than those of first-stage larva. Pores of male larva very 

 inconspicuous (PI. V, D, 2), smaller than those of female. Small quinquelocu- 

 lar type pores scattered over both dorsum and venter of body. Small tubular 

 ducts found mostly on margin. Small spines also present. 



ADULT FEMALE, THIRD IX STAR. 



Body (PI. IV, D) nearly circular and quite convex, the width exceeding the 

 depth and the length exceeding the width. Average length 1.45 mm., average 

 width 1.35 mm. General color reddish brown. Anterior half of body quite 

 heavily chitinized, particularly on margin. Derm smooth. 



Antenna? (PI. V, A, 3) no longer marginal, but occurring on ventral side of 

 body, six-segmented, slightly longer, averaging 144 /*, but similar to those of 

 second-instar larva, bearing only two of the four spines found on sixth segment 

 of first-instar larva. As in larva antennal formula varying considerably, of 

 practically no value. Average formula as follows: 6, 1, 3, (5, 2, 4). Eyes 

 lacking. 



Legs (PL V, C, 1) short and stout. Tibia and tarsus (PI. V, O, 2) subequal, 

 being together slightly shorter than trochanter and femur combined. Leg bear- 

 ing a few hairs and tarsus bearing four knobbed digitules. Usual coccid mouth- 

 parts present. Large tubular ducts (PI. V, D, 1) occurring on margin and 

 dorsum of body. Small trilocular pores and fine spines scattered over body, 

 particularly on abdomen. Anal ring (PI. V, B, 4) occurring on ventral side of 

 body, small, simple, and with six small seta? or hairs. A pair of small caudal 

 seta? one on each side of anus. Anal lobes absent. 

 150829°— 20— Bull. 838 2 



