Before the development of the aniline dyes there was no more beautiful scarlet than that obtained from the cochineal insect, a miserable coccid, allied to some of our destructive mealy bugs. As a pigment it produced a beautiful carmine, and this may make us look more leniently upon creatures like the cottony cushion and San José scales. Several of our common soft scales, notably that huge creature that infests the tulip tree, give a purplish extract in alcohol, and so do some of the Lachnid plant lice; but they will hardly be considered now-a-days as a source of coloring materials.
Insects figure to some extent in the pharmacopoeia, although not so much now as they did in days gone by. That powdered roaches had medicinal qualities was known to the ancients, and I believe that tinctures and extracts of these insects are still obtainable. Spanish flies or cantharides have a well deserved reputation for blistering properties and have been used to promote the growth of hair. They have also been made into extracts and tinctures, and used internally for a variety of troubles.
Bees produce an acid that is useful in some rheumatic affections, and it is asserted that the simplest effective method of application is to allow the bee itself to administer the remedy directly to the affected part. Incidentally, by this method the patient gets back at the operating physician, for whether the patient is benefited or not, the administrator dies as the result of the application.
But decoctions and other preparations of insect species are no longer so much thought of as in days gone by, and we now run to sanitation and other preventive measures, to serums and antitoxins, to antiseptics and to coal-tar products, so I need hardly claim very much more for insects under this head.
I might mention that insects as food material are not unknown, and while I have already mentioned locusts as a plague, I might add in mitigation that they also serve as an important article of food for the natives in the countries where they occur in such numbers. Wood-boring larvæ and even insect eggs have been and are even yet eaten; but their value in these respects can hardly be deemed sufficiently great to give them a favorable standing in our present communities.
Indirectly valuable to man are a long series of species that act as scavengers, reducing dead animal and vegetable matter to its inorganic compounds, and another series that serves as an aid to plant propagation. The former need little attention because man can do scavenger work much better and quicker himself; but in the work of plant pollination the importance of insect work is scarcely appreciated by the public at large.
Numerous plants depend absolutely upon insects for continued existence, and there are all stages of dependence from those where the
