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HINTS FOR THE PROMOTION OF ECONOMIC ENTOMOLOGY. 717 
scriptive and systematic portions of our science, and conclude with 
those relating to its future usefulness. 
First, then, will come the completion of the series of works, pub- 
lished by the Smithsonian Institution, on the classification of the 
several orders. For this students must be found, who will devote 
themselves to the study of those orders which have been here- 
tofore neglected. This series must be supplemented by synony- 
mical and bibliographical catalogues, and finally by synopses of 
species in each order to which supplements from time to time must 
be made, to diminish as far as possible the necessity of reference 
to other works, and thus place the accurate results of science 
within reach of persons who can ill afford the costly libraries now 
necessary for reference. 
Second, and equally important, will be the formation of type 
collections for the identification of species. The number of 
species is so vast, the differences so small, and the multitude 
of new forms, not yet represented in collections, so great, that 
the best descriptions that can be written do not obviate the ne- 
cessity of referring at-times to the original types for comparison, 
and the amount of time, labor and expense saved to students, by 
having the whole of the information within reach at one place for 
each order of insects, can scarcely be estimated. 
These type collections should be in the possession of the stu- 
dent who can make best use of them for the present interests of 
science, and on his death, or retirement from intellectual pursuits, 
should not be exposed for sale, or to any other vicissitudes of for- 
tune, but should be given to his successor in science, or placed in 
some public institution where they will be most carefully preserved 
and used only for reference. 
The liberality of friends, both at home and abroad, has already 
made my collection of coleoptera such a type collection, and with 
the exception of a moderate number of species described in Europe, 
of which no duplicates can be obtained, and a very small number 
which I have described from other collections, at the solicitation of 
their owners, it contains types of nearly all the described cole- 
optera of America north of Mexico. From the saving of time 
both to students who visit my collection, and to myself in naming 
series for correspondents, I cannot too strongly recommend the 
formation of similar collections in other orders of insects.* 
* As a proof of the earnestness of this recommendation, as well as a duty I owe to 
; _ those interested in the progress of the science, who have codperated with me in plac- 
