266 DRY ROT. PART n. 



and the Merulius lacrymans or common house fungus, 

 attacks and induces the decay of timber previously 

 sound. The cap is large, fleshy, spongy and moist, but 

 delicate and velvety on the under-side, with wide porous 

 dentate folds. The plant is yellow with a white woolly 

 margin. It grows in a circle, and its mycelium attracts 

 moisture from the atmosphere, which falls down in drops 

 from the pileus. The decay of wood induced by the at- 

 tacks of this mischievous fungus, is what is called dry rot. 



The four principal sub-orders of the Hymenornycetes, 

 or highest fungi, have a cap or pileus, and an inferior 

 fructiferous surface characterized by gills, pores, or 

 tubercles, and are connected by intermediate species ; 

 but the other two sub- orders are quite different. The 

 Clavariei are club-shaped, upright, branching fungi, 

 with the fructification surrounding the uppermost ex- 

 tremity of some of the stems. The finest species grow- 

 in the Swiss forests where they form an article of food ; 

 some are edible in Britain, but of smaller size. 



The Tremellini consists of plants forming a gelatinous 

 mass of a bright orange, purple, or dark brown colour, 

 which may be seen on rotten sticks in hedges, and in 

 enormous masses resembling the convolutions of an 

 animal's brain on the stumps of dead trees, or at the base 

 of living ones. They are mostly plants of temperate 

 climates, but the Exidia Auricula Judse, or Jew's ear, 

 is universal. All fungi have a mycelium, but in this 

 order it is not apparent. The structure of the fruit, 

 as determined by the microscopic observations of Mr. 

 Berkeley and of M. Tulasne, is unusual. The fructiferous 

 part is very extensive, being uppermost and spread over 

 the surface of the gelatinous mass, so as to follow all its 

 inequalities. Threads rise from this fructiferous surface 

 bearing on their extremities globular cells exhibiting 

 a concentration of coloured matter generally divided 

 into four lobes, and from the upper surface of these 



