Page:An introduction to physiological and systematical botany (1st edition).djvu/540

 510 since his death by the acquisitions of his son and of its present possessor.

One great and mortifying impediment to the perfect preservation of an herbarium arises from the attacks of insects. A little beetle called Ptinus Fur is, more especially, the pest of collectors, laying its eggs in the germens or receptacles of flowers, and others of the more solid parts, which are speedily devoured by the maggots when hatched, and by their devastations paper and plants are alike involved in ruin. The most bitter and acrid tribes, as Euphorbia, Gentiana, Primus, the Syngenesious class, and especicially Willows, are preferred by these vermin. The last-mentioned family can scarcely be thoroughly dried before it is devoured. Ferns are scarcely ever attacked, and grasses but seldom.—To remedy this inconvenience I have found a solution of corrosive sublimate of mercury in rectified spirits of wine, about two drams to a pint, with a little camphor, perfectly efficacious. It is easily applied with a camel-hair pencil when the specimens are perfectly dry, not before; and if they are not too tender, it is best done before they