Bot. Char. The word Boletus, which has at different times, and under different mycologists, been made to represent in turn many very different funguses, is now restricted to such as have a soft flesh, vertical tubes underneath, round or angular, slightly connected together and with the substance of the pileus, open below, and lined by the sporiferous membrane; the cap horizontal, very fleshy, the stalk generally reticulated, some have an investment; the flesh of many changes colour.
They are all innocuous, according to Vittadini, which is not strictly the case, though many species hitherto reputed unwholesome, or worse, appear to lose their bad properties by drying. The kinds generally eaten are B. edulis and scaber.
Genus 8. FISTULINA.[149]
Bot. Char. Hymenium formed of a distinct substance, but concrete with the fibres of the pileus; tubes at first wart-like, somewhat remote, radiato-fimbriate, closed; at length approximated, elongated, open.
Esculent species: F. hepatica.
Genus 9. HYDNUM.[150]
Bot. Char. In this genus the under surface presents a series of conical teeth or bristles of unequal length, solid, continuous with the flesh of the pileus and covered entirely by the sporiferous membrane. The species composing it have no investments; the flesh is dry, frequently corky or coriaceous; the pileus irregular in shape, and its margin arched and undulated. There are no dangerous species, but which to eat must depend upon the united consent of the stomach and of the teeth.
Esculent species: H. repandum.
[In the last five genera of this tribe, namely, Sistotrema, Irpex, Radulum, Phlebia, and Thelephora, there are no esculent species.]