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certain peculiarities of hal)it will render an insect proof against measures which at 
first sight ajrpear to he entirely practicable. Methods of spraying and combinations 
of substances for this purpose have been tested and experimented with to a consid- 
erable extent by men who are not trained entomologists, and, in many cases, to very 
decided advantage in the production of mechanical devices for spraying and com- 
binations of insecticidal substances, but in some cases the attempted application of 
such methods or combinations to certain kinds of insects would be recognized as 
useless by anyone acquainted with the fundamental structure of insects. 
While we would encourage therefore every effort toward the perfection and adop- 
tion of spraying devices and spraying fluids, we would urge the importance of refer- 
ring the application of these to various insects whose habits are not entirely known 
to trained entomologists who should be able to determine as to the possible value or 
usefulness of the effort and the direction of practicability for such measures. That 
the entomologist connected with an experiment station should devote himself to the 
investigation of the injurious insects in his territory would seem to require no argu- 
ment, but there are cases in which we see entomologists in their capacity as station 
workers devoting themselves to studies which, to say the least, have but a very 
remote relation to the practical needs of their constituency. While a knowledge of 
the insect fauna of each particular State is a great desideratum and is ultimately of 
economic importance, it seems to me that to make this the leading subject of study 
to the exclusion of the study of the habits of the known destructive forms is a mis- 
take. To take up the investigation of monographing of a group of insects, which, 
in their distribution and habits, have little relation to the industries of his State, is 
unwarranted. For the person engaged as an experiment station worker to engage 
in the monographing of a group of marine mollusca would be manifestly absurd, but 
instances not greatly different from this could be cited from the history of our exper- 
iment stations. It must be remembered, of course, that there are a number of 
instances in which the station entomologist is simply to devote part of his time to 
station work and part to other duties, and if such work is embraced among his other 
duties this remark would have no application. It should be understood thoroughly, 
however, that it is a matter of common honesty for an individual engaged for a 
certain kind of work to devote himself thoroughly to that particular work. 
In the method of work which he investigates the entomologist should aim above 
all to secure thoroughness and accuracy, and for this purpose he needs a full equip- 
ment of apparatus, the particular character of which will depend upon his location 
and the subject of study, but in the provision of which ho should not be stinted. 
For the full elaboration of life histories some form of insectary is almost essential, 
although, of course, much work may be done without the complete control of condi- 
tions which may be provided by such a building. Of breeding cages he should have 
a fall supply, and these will be constructed in varying degrees of complexity, accord- 
ing to the results to be reached. He must not omit the study of minute details in 
structure or a careful determination of species and varieties, as this may happen to 
be an important factor in the determination of methods of work, danger of intro- 
duction and distribution of certain species, and other points of importance, all of 
which can not be exaggerated. A complete equipment for thorough microscox>ic 
work is therefore of absolute necessity, and no entomologist should consider his 
equipment complete, or even begun, without such an outfit. While a great number 
of insects which he is called upon to examine may be readily determined without the 
use of the microscope, there are many in which the microscopic characters are an 
absolute necessity. For instance, the necessity of such work occurs in the recent 
distribution of the San Jos6 scale, which has been of such immense importance in 
California, and which during the last two years has been recognized at a number of 
localities in the Eastern States. The extensive notices given to the distribution of 
this species naturally led to an examination of orchard trees all through the fruit- 
growing districts, and many specimens of the common native bark lice were sent to 
our experiment station for identification, and doubtless the same occurred in nearly 
