Tab. 410, On October 12, the same year, William Lewis, Esq. sent me from Hendon, the leaves of a Charmontelle pear-tree, which grew against an open fence, the inclination of which was to the South-East. The upper surface of these leaves contained, to all appearance, the same parasite as above, in the older or latter state; and immediately under it, as it were, the lower half of the leaf Mas swelled into irregular protuberances, more prominent than the conical forms on the opposite side, including in their centres a sort of capsule, which in the more central ones of the group emerges from them more than half its length, the apex of these have a central knob or embossment, from which a number of filaments descend, giving it a somewhat pyriform appearance, a line in length, forming to the base, or being divided in peculiar lines, so as to allow seeds to pass out, which were apparently arranged in order upon them as upon a receptacle.
This Fungus, which grows under the leaves has been considered a distinct species; but from these specimens it seems scarcely doubtful that they are analogous to the dioecious class of plants, and are of one and the same species. Those on the upper side of the leaf might have been considered, if alone, as a Sphæria, but as they may belong to tbe opposite parasite, they must be included as one dioicous species.
Monsieur De Candolle speaks of the upper one as being in points or spots opposite and attendant on the under one. The peculiarities of particular Fungi will afford much entertainment, but proper research would take up more agreeable time than falls to my lot at present.
