28 
Present State of Noxious Insects. (Trans. Ill. State Hort. Soc.. 1872, N. Ser.. 
v. 6, pp. 257-262.) 
Insects vary extremely in the method and degree of their prevalence. 
Their multiplication at times is astonishing. The two of greatest interest 
to horticulturists of Northern Illinois are the oyster-shell bark louse and 
the cankerworm. These bark lice are diminishing through the agency ol 
Acari and a chalcid. In some of the more northern sections, these enemies 
seem wanting. Describes an attempt to transport the chalcid to that 
region. [See (p. 29) “Transportation of Useful Parasitic Insects." 3d Rep. State 
Ent. Ill. (fourth of series).] Discussion on cankerworm, and on coal tai 
and other insecticides. 
Lecture on Insects. (5th Ann. Rep. Board of Trustees 111. Industrial Univ. 
1871-72, pp. 193-200.) 
Mentions the importance of practical education and the place of agri¬ 
culture and its collateral branches. Among these the science of ento¬ 
mology holds no insignificant place. The extensive cultivation of certain 
plants has been followed by an excessive increase of some of their insect 
enemies. Examples cited from past seasons, among them the chinch bug 
which, over a territory one hundred miles wide, commencing in Western 
Indiana and extending more than four hundred miles westward, has re¬ 
duced spring wheat to about a quarter crop, barley to less than half n 
crop, and oats to not more than three quarters of a crop.—a loss ol 
about $10,000,000 for Illinois and $30,000,000 for the Northwestern States 
Number of injurious species of insects in the country is about one hun 
dred. Whole number of species in Illinois is about 20.000. Two principa 
methods of counteracting insect injuries: by direct attack and destruc 
tion of them: and by obtaining and making use of a knowledge of then 
habits. To illustrate the latter, remedies for the oyster-shell bark louse 
Saperda bivittata, Hessian fly, and Colorado potato beetle are given anc 
explained. Uses of insects noted and illustrated. 
Introduction. (3d Ann. Rep. State Ent. Ill. [fourth of the series], Part 1st 
pp. v-vii.) 
The State Entomologist is expected to advance the scientific as well a? 
the practical interests of the State. The recent introduction of natura 
history into the public school creates a need for. elementary treatises 
Hence a work of this kind is here begun. Further notes on the content! 
of this report. 
Insects Injurious to the Apple. (3d Ann. Rep. State Ent. Ill. [fourth of th< 
series], Part 1st, pp. 167-192.) 
The Codling Moth or Apple Worm (pp. 167-185: Prairie Farmer, Maj 
24. 1873, v. 44, p. 161; Ibid., June 7, 1873, p. 178).—Among fruit-damaging 
insects this one holds the first place. It hibernates as a larva in cocoon: 
under bark or in fissures of the tree and pupates within two or threi 
weeks of its appearance as a moth in the spring,—the summer broo( 
wuthin a few r days after spinning cocoons. Moths appear in the spring 
about the time the apple blossoms open, earlier southward, at the rate o 
about one week for each hundred miles of latitude. Eggs are placed in th< 
calyx end of young apples, and hatch in the course of a week. Young 
larvae described. Subsequent history outlined. Length of life in th< 
several stages given. The following points noted: As a general rule, bui 
one egg is laid on each apple, though another is frequently added by i\ 
second moth, especially among the second brood. Eggs, about fifty in eacl 
female, unequally developed, lienee not all laid at once. Imagos live abou 1 
a week. .They feed in confinement on sugar and apple. Appears to be one 
brooded in more northern localities. Practical treatment grouped unde 
four heads; destroying the insects in their winter quarters, picking worm: 
apples from the tree, gathering wormy apples from the ground or letting 
swine and sheep have the range of the orchard, and entrapping the w r orm 
in bands or other contrivances. Natural enemies are the woodpeckers, twe 
species of ichneumon fly, a Trogosita, and Arma spinosa. Experiments t( ] 
