14 CALIFORNIA STATE COMMISSION OF HORTICULTURE. 



Subfamily MARGARODINiE. 

 Xylococcus quercus Ehrh. 



The specimen taken in October is very dark in color, blackish, the 

 markings being only faintly indicated. 



Egg quite large, of a light orange color. 



Young larvae dark orange-red, active, body broadly oval, about f mm. 

 long. Legs and antennae light brown, well developed. Antennae short, 

 6-jointed. Joint 1 stoutest, joint 6 longest, and joint 4 shortest. 

 Formula: 6 5 12 3 4. Joints 2 and 5 with three bristles. Joint 6 with 

 numerous long stout bristles. Legs moderately long, with femur quite 

 swollen. Tarsus longer than tibia. Digitules of tarsus fine hairs; those 

 of claw long stout clubs curved upward. Each segment of abdomen 

 bears a backward-directed short stout spine. On each side of anal tube 

 is a long fine bristle. Anal tube large, with numerous stout spines. 

 Stigmatal tubes well developed. ' 



Female (second stage). — Body crimson, shiny, nearly spherical, about 

 li mm. long, 1 mm. broad, surrounded by cottony and waxy secretion. 

 Antennae and legs wanting. Anal tube well developed, producing a 

 glassy rod, like a stout white hair, rather brittle. Last segment of body 

 dark brown. When cleared in KHO, surface of body finely granulated, 

 more so near caudal end. Stigmatal tubes are large and well defined. 

 There are numerous spines and gland openings scattered over the body. 



Third and fourth stages very similar to second stage, but larger in 

 each case than the preceding, and varying in the further development 

 of stigmatal and anal tubes, glands, spines, etc. 



Adult Female. — Head, thorax, legs, and antennae reddish brown, 

 abdomen blackish brown, segmentation distinct. There is a distinct 

 constriction between the thorax and abdomen. Length of body about 

 5i mm., breadth 2^ mm., quite convex above. Ventral side of abdomen 

 concave, with revolute margins. Insect quite active. When ready to 

 deposit eggs crawls into some crevice and produces a cottony cushion, 

 on which it rests and secretes considerable white cotton over its entire 

 body. Antennae 9-jointed. Joint 1 longest and broadest, next in length 

 is 2, then joint 9, and then 3. Joints 4, 5, 6, 7, and 8 are subequal, and 

 are a little shorter than 3. Formula: 1 2 9 3 (4 5 6 7 8). Legs long and 

 stout. Tibia twice as long as tarsus, both very hairy. Claw long and 

 stout. Digitules fine hairs. Body sparsely covered with long stout 

 spines, especially along the margin and caudal end. Stigmatal tubes 

 very prominent. Anal opening simple and quite large. 



Adult Male.— About 3 mm. long and 1^ mm. broad, slightly pubescent. 

 Color of abdomen reddish brown. Mesothorax black, with four raised 



