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are to be found among the Hymenoptera or membrane-winged insects. It is on 
account of the highly developed instincts, exhibited in the care they take in pro- 
viding for their young and in laying up stores for winter use, added to the 
important part they play in the fertilization of many plants, that they have been 
placed first in Dr. Packard’s system of classification. I shall speak later on of the 
relations between insects and plants, and will now direct your attention to a few 
points in the life history of insects which have seemed to me to be of more 
interest than usual. 
By far the larger proportion of these insects are beneficial, and feed either 
in the larval or perfect state upon other insects. Of beneficial insects mention 
must first of all be made of the honey bee, concerning which aione whole volumes 
have been written; and afterwards of the various wasps and allied genera which 
feed upon and store up for the sustenance of their grubs, enormous numbers of 
caterpillars, and other insects, as well as acting as scavengers. Among the social 
bees, wasps and ants, there are found not only males and females, but also other 
kinds of individuals which are necessary for the successful propagation of the 
species ; these are called neuters, and sometimes laborers or nurses; they are, 
however, essentially females, having the female organs, but in an imperfectly 
developed and } assive state, their sting being only an accessory part, which is 
changed into a special weapon of defence, and is the homologue of the ovipositor 
in fertile femaleinsects. The worker bee, besides collecting the honey aud pollen 
which is to serve as food for the offspring of the queen, has to carry the eggs 
from the queen to their proper cells and feed the larve when they are hatched ; 
they are therefore indispensable for the propagation of the race. 
I class wasps among beneficial insects, because the sting ior which they are 
dreaded is never used against man, except as an instrument of defence, while its 
proper use is the destruction of his enemies, the caterpillars of numerous noxious 
species of insects. 
Although some members of the wasp family do fill their cells at certain 
periods with honey, the food of the greater part, undoubtedly, consists of animal 
matter, chiefly other insects, which they either seize with their mandibles, or, 
when it is to be stored away for the use of the larve, sting todeath. The poison 
introduced by the sting owes its virulence to the presence of a peculiar acid known 
as formic acid. This acid is said to be chemically very similar to chloruform, and 
its action upon insects stung to death is very peculiar. It does not kill them at 
once, but paralyzes them, so that they live for many days, and, in some cases, 
jarve have been known to turn into pupe after having been stung, but have not 
had sufficient strength to complete their final change into imagines. The use of 
this antiseptic property of the poison is easy seen. The mcther wasp, having 
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