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chinch bugs sufficiently free from it to make them suitable subjects for experi- 
mental attempts at its transfer. It will be readily understood by any one that it is 
useless to test the utility of artificial cultures of the disease germs by applying them 
to insects which are already affected by the disease in question. The first step of 
any really scientific investigation of the economics of this matter is to determine 
positively the absence of the disease in the lots of insects to be used in the experi- 
ments. Every lot of chinch bugs thus far obtained by me from central, south cen- 
tral, and northern Illinois during the months of July and August of this year gave 
evidence, under critical study, of the presence of this microbe in the ceca of 
a larger or smaller percentage of pup and imagos. My previous observations—less 
carefully made, however, than my recent ones—have been to the general effect that 
hibernating chinch bugs and young preceding the so-called pupa state are little 
liable to the spontaneous occurrence of the intestinal trouble, and I consequently do 
not despair of finding, before the present season is over, opportunity for experiments 
which will determine beyond question the economic value of this chinch bug 
cholera. 
In comparing this with similar human diseases we must take account of the 
poverty of the circulatory fluid of the chinch bug and the simplicity of its circula- 
tory apparatus, which forbid the marked development of any of their phenomena of 
fever or inflammation. Indeed, it seems to me that insect diseases generally are 
characterized by the absence of a vigorous physiological reaction which their rela- 
tively low structure, nervous and circulatory, makes impossible. The features of 
this disease, for example, I think may be wholly accounted for, consistently with the 
physiology of the insect, as results of the simple destruction of the epithelium of the 
coeca and the consequent suppression of the functions of those organs, combined 
with the toxic effects of the products of bacterial action. 
Is it not quite possible that the student of pathology may find in the study of the 
diseases of those lower forms of life, experiments prepared for him by Nature which it 
would be quite impossible for him to imitate on animals of more complicated sensi- 
tive and sympathetic organization; and that he may thus sometimes simplify a 
problem whose complexity must otherwise prevent its solution? 
Injurious Insects of New South Wales.—Since we last referred to the 
entomological matter in the Agricultural Gazette of New South Wales, 
we have received parts 4, 5, and 6 of volume 11. Mr. Olliff has, in part 
4, an interesting article on the Fig Leaf Beetle (Galerucella semipullata), 
a species which feeds in all stages on the young shoots and foliage of 
wild and cultivated figs. Figures of all stages are given, as well as a 
detailed account of the life history. Spraying with Paris green is rec- 
ommended as aremedy. In part 5 the same author treats of a Tachinid 
parasite of the Plague Locust, figuring it in all stages, and giving a 
technical description by Mr. F. A. Skuse under the name Masicera 
pachytih. This parasite has appeared in great numbers, and in one 
locality from 60 to 70 per cent of the grasshoppers were affected by it. 
He also makes some mention in the same number of a species of Chermes 
on Pine, the Oyster-shell Bark-louse of the Apple, and the Orange Rust- 
mite, In part 6, Mr. Olliff publishes an account of the Pine Case-moth, 
Orketicus huebneri, with a full-page plate illustrating its transformations. 
It is closely related to the Bag Worm of the United States, and has 
