6

OUTLINES OF BRITISH FUNGOLOGY.

In some of the species of Gill-bearing Fungi, especiallywhere the substance becomes tough and hard, there is a ten-dency in the gills to run into each other by means of lateralprocesses or veins, and so to make pores. The Fungi of thisfirst division are known under the general name of Agaricini,or Mushroom-like Fungi. Almost all the species are of con-siderable dimensions ; a very few only, as the pretty holly-leafAgaric, with its long bright bristles, require a common lensto see their beauty.

In a very important group of Fungi, however, the pores arethe essential character, as the gills are in those we have justdescribed. These pores may be partially or entirely free, asin the genus* Fistulina (Plate 17, fig. 1), with which mostare familiar under the form of the dark-red Fungus which isso common on the trunks of old oaks, and which when di-vided looks very like beet-root, the whole plant resemblingan ox-tongue. In general however they are closely packedand more or less intimately united, sometimes separatingeasily from each other, and sometimes inseparable. Theformer condition occurs in the most characteristic genus ofthe group, Boletus (Plate 15, fig. 4, 5, 6), which under a varietyof forms adorns our woods or the scanty herbage under oldtrees, more rarely appearing on hedgesides, or in the openfields. Under fir-trees a bright-yellow species is extremelycommon, and one of a more sombre tint where larch is pre-dominant. Sometimes they grow in conspicuous rings, andsometimes they attract notice from the instantaneous changewhich they undergo, when broken and divided, from white oryellow to deep blue. This change was long a source of per-plexity to those who examined it, but it is now known to de-pend upon the action of ozone upon the juices.

* This genus is indeed sometimes associated, but wrongly, with the generaof the next division.