6 OUTLINES OF BRITISH FUXGOLOGY. 



In some of the species of Gill-bearing Fungi, especially 

 where the substance becomes tough and hard, there is a ten- 

 dency in the gills to run into each other by means of lateral 

 processes or veins, and so to make pores. The Fungi of this 

 first 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-leaf 

 Agaric, with its long briglit bristles, require a common lens 

 to see their beauty. 



In a very important group of Fungi, however, the pores are 

 the essential character, as the gills are in those we have just 

 described. These pores may be partially or entirely free, as 

 in the genus^ Fistulina (Plate 17, fig. 1), with which most 

 are familiar under the form of the dark-red Fungus which is 

 so common on the trunks of old oaks, and which when di- 

 vided looks very like beet-root, the whole plant resembling 

 an ox-tongue. In general however they are closely packed 

 and more or less intimately united, sometimes separating 

 easily from each other, and sometimes inseparable. The 

 former condition occurs in the most characteristic genus of 

 the group, Boletus (Plate 15, fig. 4, 5, 6), which under a variety 

 of forms adorns our woods or the scanty herbage imder old 

 trees, more rarely appearing on hedgesides, or in the open 

 fields. Under fir-trees a bright-yellow species is extremely 

 common, and one of a more sombre tint where larch is pre- 

 dominant. Sometimes they grow in conspicuous rings, and 

 sometimes they attract notice from the instantaneous change 

 which they undergo, when broken and divided, from white or 

 yellow 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 genera 

 of the next division. 



