29 
ietermine time of leaving apple, show that about one half drop to the 
ground, and the other half descend the tree. Time of examining bands 
iiscussed. 
The Yellow-Necked Apple-tree Caterpillar (pp.186-192).—Moth and larva 
lescribed. Life history and habits treated. Food plants mentioned. They 
winter as pupae and appear as adults at different times, from June 1 Otli 
to as late as July 18th. This insect presents one of the best examples of 
phytophagic variation, Different varieties compared and experiments of 
3 hanging fooci plants mentioned. Seems to think, with Walsh, that varia¬ 
tions cannot be relied upon as specific characters. Their gregarious habits 
make it easy to gather and burn them while feeding or molting. 
Insects Injurious to the Cottonwood. (3d Ann. Rep. State Eut. Ill. [fourth of 
the series], Part 1st, pp. 193-199; reprinted in part in Prairie Farmer, 
June 28, 1873, v. 44. p. 201.) 
Poplar-leaf Gall-louse {Pemphigus populicaulis ).—Forms a gall, most 
abundant on lower branches, of the size of a small marble, at the base of 
the leaf of the cottonwood. The galls are formed by a little fold of the 
leaf which subsequently enlarges, but the edges or the fold never unite. 
They are formed in May. Each gall is occupied by a single wingless fe¬ 
male, which by midsummer produces a numerous progeny. Black eggs 
found in fall imbedded at base of buds. A curious habit of throwing 
liquid globules from the galls mentioned. Anthocoris musculosus , a chalcid 
larva, a Syrphus larva, and an ichneumon larva are found in the galls 
late in the season, and greatly reduce their numbers. 
Divides plant lice into four sections. First, the leaf-lice, with antennae 
and honey tubes long, living on foliage and new growths. These are very 
sensitive to weather changes. The common remedy is fumes of tobacco. 
Second, the twig-lice (Lachnus), with short honey tubes and 6-jointed an¬ 
tennae, on smaller limbs of certain trees. Third, the root-lice, with an¬ 
tennae short and honey tubes wanting, infesting roots, and the most seri- 
jus pests. Infested roots should be dipped in hot soap-suds or tobacco 
water. Fourth, the gall-lice. These are difficult to kill, but do not seri- 
eusly attack any fruits except the grape. The populicaulis gall is mostly 
an the lowest branches, while that of P. vagabundus is often seen on the 
topmost twigs. Other examples of similar habits mentioned. Such facts 
may be turned to account in combating noxious insects by removing the 
portion attacked. 
Transportation of Useful Parasitic Insects. (3d Ann. Rep. State Ent. Ill. 
[fourth of the series], Part 1st, pp. 200-202: Prairie Farmer, July 27, 
1872, v. 43, p.-.) 
Chalcis mytilaspidis is a destructive parasite of the oyster-shell bark 
louse. The fact that one brood hibernates as a larva beneath the scales, 
suggested the possibility of conveying it while in that condition to in¬ 
fested regions not yet reached by it. Early in the spring of 1871, a bun¬ 
dle of twigs with parasitized scales was taken to Galena and the twigs 
tied upon infested trees in three different orchards. About one year later, 
a few holes, probably those of a chalcid, were found on twigs from some 
of the trees. On July 13, one of the experimental trees was thoroughly 
examined, and showed a considerable number of scales perforated by chal- 
cids. The results, if not conclusive, were extremely encouraging. 
Outlines of Entomology. Insects in general. (3d Ann. Rep. State Ent. 111. 
[fourth of the series] part 2d pp. 1—37: reprinted in the 4th Ann. 
Rep. State Ent. Ill. [fifth of the series]. 1874, pp. 1-37.) 
Subject extensively discussed under the following headings: 
Insects in general. 
Internal structure of insects. 
Nervous system, circulatory system, respiratory system, digestive 
system, secretory system, muscular system. 
Organs of the senses. 
Sounds produced by insects. 
Metamorphoses of insects. 
