THE COCCIDAE OF CALIFORNIA. 27 



7- jointed, joint 7 longest; sometimes joint 1 is next longest, but joint 

 2 is often longer than joint 1, and in many cases they are sub- 

 equal; joint 6 usually next, although joint 3 may be longer than 

 6; joint 4 next, often subequal with 5; sometimes 3 shortest, sometimes 

 5; 3 and 5 often subequal. In fact, the sequence of the joints is 

 quite variable, as is shown in the following antennal formulae: 

 721(36)(45). 7(12)6(45)3. 71264(53). 7(12)64(53). Joint 

 1 is stouter than any of the others. Each joint with hairs, joint 7 

 with several stout hairs. Legs light brown, large and stout; each joint 

 furnished with one or more rather long bristles. Femur, 80X50^; 

 tibia, 70 yw; tarsus, 50 ^] claw, 20^. Digitules of claw knobbed, moder- 

 ately short and stout. Tarsal digitules long, fine, slightly knobbed 

 hairs. Tubercles small and rounded, with long stout bristle. Anal 

 ring with six stout hairs. 



Larva, when newly hatched, color light red, rostral loop extending 

 beyond body. 



On Quercus agrifolia. 



Subfamily COGGING. 



Pulvinaria innumerabilis Rathv. 



This scale insect somewhat resembles the cottony-cushion scale 

 (leery a purchasi) and is often mistaken for it. It can be easily dis- 

 tinguished, however, 

 being much smaller 

 and the general ap- 

 pearance differing 

 materially. 



Female . Oval in 

 form; color dark 



brown Near the DOS- FIG ' 9 ' Pulvinaria innumerabilis (Cottony Maple Scale). 



On Grape. 



tenor end are ridges, 



and the lines that separate them are darker than the other parts. The 

 eggs are laid in the cottony sac; they are white when first laid, but 

 change to a yellowish tinge before hatching. They are oval in form. 

 The larva is yellowish white. 



At one time this species was very troublesome, but the internal para- 

 sites Coccophagus lecani and Encyrtus flavus work on this pest most 

 effectively in the larval form, and the Rhizobius ventralis clean up the 

 egg sacs of those that escape the attack of the parasites in the larval 

 form and mature. 



The other species of Pulvinaria found in California are of no economic 

 importance. 



