OAK SCALE-INSECTS. 103 
53. Rhizococcus quercus Comst. 
(Plate xxix, Fig. 2.) 
The following account of this scale insect is by Professor Comstock 
(Agricultural Report, 1880) : 
Female. — The tubular spiuueret9 are more numerous thau iu R. araucaria, and are 
not confined to the margin of the body, but are distributed irregularly over the dor- 
sum. They vary much in size and are curved and acuminate (Fig. 2a). Tarsi less 
than one-half as long as tibiae. Hair on. trochanter nearly as long as femur. 
Male. — I have only one specimen, which is much shriveled; this resembles R. 
araucarice, except that the ocelli are placed farther caudad of the eyes than in that 
species. 
Described from 17 females, 1 male, and very many larvae, all mounted in balsam. 
Habitat. — On scrub oak at Rock Ledge, Fla. ; upon gall-berry, oak, and grass at 
Fort George, Fla. (Dr. R. S. Turner). The sacs (Fig. 2) of this species, ofVhich I 
have very many specimens, very closely resemble those of R. araucarice. The sacs of 
the female are all large, indicating that the species is naked till full grown. 
The following observations are from Prof. Riley's MS. notes: 
Specimens of this coccid were received March 29, 1882, from A. Koebele, Archer, 
Fla., infesting both the trunk and twigs of live oak. Males were just issuing in con- 
siderable numbers when received. Their color is reddish, eyes black, antennae and 
legs paler red, thoracic band black. Wings faintly yellowish, somewhat iridescent, 
with the veins slightly darker. The whole insect is covered with a delicate whitish 
layer of a mealy excretion. The white anal filaments are louger than the whole 
insect, including the antennae. The young females are dull greenish yellow. The 
old females are purplish, and the eggs pale purplish. Some of the scales were in- 
fested by Dakruma coccidivora, and others by the larvae of a Scymnus which were 
feeding on the eggs. 
The following observations, which relate to this or an allied species, 
are also copied from Prof. Riley's MS. notes : 
March 1, 1830, received from Dr. J. H. Mellichamp, of Bluffton, S. C, some twigs 
of Quercus myrtifolia infested by a coccid. The scales are white and have a silky ap- 
pearance ; they are mostly oblong-oval in form, but sometimes shorter. . The eggs 
under these scales are regularly oval, whitish pink in color, opaque, semi-transparent, 
without visible sculpture, and held together by short, interwoven threads that some- 
what resemble cottou batting. The scales are found in clusters at the base of the 
more slender twigs, others single, while a few stray to the leaves. One cluster of 
these scales was infested by a lepidopterous larva about two-thirds of an inch in 
length and of a dirty greenish-gray color. This larva kept concealed under the 
scales and wherever it pierced them it closed up the holes with a delicate web. It 
spun for itself a silken cocoon, March 3, at the bottom of the jar and issued on April 
19. The eggs of the coccid hatched from the 6th to 20th of March. All died. 
54. Chionaspis quercus Comstock. 
(Plate xxvm, Fig. 3.) 
This scale insect, according to Professor Comstock (Ag. Rep. 18.80),- 
lives on white oak (Quercus lobata) in San Fernando Valley, California. 
