19 



Fig. 13.— Pulvinaria 

 acericola: male 

 pupa, greatly en- 

 larged (original) . 



composing the sac began late in May and continued gradually until 

 nearly the middle of June. Larvae began to hatch on June 13. 



The newly hatched larvae are of a very pale yellowish color, with 

 median line slightly brownish, and the eyes dark purple. 

 The antennae are six-jointed, joints 3 and 6 longest and 

 subequal in length, 4 and 5 also subequal and together 

 about as long as joint 3; the two basal joints are also 

 subequal, each about as long as joints 4 and 5, the first 

 joint being stoutest. There is a bristle near the apex 

 at the inner side of joints 3 to 5, and several at both 

 sides and apex of the sixth joint. The digitules of the 

 tarsi are extremely fine; those of the claws stouter and 

 shorter; and all are capitate. Anal bristles are long 

 and curved. The surface of the body is densely rugose, 

 especially toward the sides; and the edge of the body 

 is closely and sharply serrate. 



On July 3L the larvae commenced to cast their first 

 skin. They were still of a very pale yellowish white 

 color and almost transparent, though a very few speci- 

 mens were marked near each end of the body with a 

 pale purplish spot. In other respects they resembled the larvae of the 

 first stage except that they were a little longer and broader. The 

 antennas were still six-jointed, though somewhat longer than before; 

 legs and their digitules as before; the bristles around the edge of the 



body were somewhat longer than in 

 the first stage, but the anal ones 

 were much shorter and but slightly 

 longer than the others; all were 

 situated on small cylindrical tuber- 

 cles which, however, were slightly 

 enlarged at the apex. 



The growth from this time was 

 very slow, and not until October 

 was the second skin cast in the 

 year of 1899. In 1898, however, a 

 tew larvae of this third stage were 

 observed as early as July 26. In 

 1899, many by October 15 had 

 already left the leaves and had set- 

 tled on the twigs. They were of a 

 pale brownish yellow color, some- 

 what darker along the medio-dorsal 

 ridge, and were characteristically 

 marked with a large reddish, almost 

 crimson, medio dorsal spot on the prothoracic segment, and a similar 

 spot just in front of the anal cleft. The eyes were minute and black. 

 They were nearly twice as large as before, and at this time the sexes 



Fig. 14. — Pulvinaria acericola: late hibernating 

 female, greatly enlarged ; natural size on twig 

 at right (original) . 



