DISCOID FUNGI— DISCOMYCETES 185 



Then there is the well-known Peziza aurantia, three inches in 

 diameter, growing amongst grass, several orange si^ecies of 

 Humaria scarcely a quarter of an inch in diameter, growing on 

 the naked soil, and in both cases with a smooth external 

 surface. Compare these with the orange or red species of 

 Scutellinia which flourish on wood and have the exterior 

 covered with brown bristles. Does the colour serve the same 

 purpose in all, and, if so, why are the species of Humaria 

 smooth and those of Scutellinia covered with bristles ? These 

 are problems not easily solved, because the substratum of fact 

 is imperfect. It will not serve to assume that the bright 

 colour is an attraction to insects, since it is not known that 

 the visits of insects would be of much service to the Fungus. 

 If there is no known process of fecundation there will be no 

 cross fertilisation to accomplish, and the dispersion of the 

 sporidia is assured by the elasticity of the asci and the force 

 with which the sporidia are seen to be expelled in a little 

 cloud, puffed out at intervals under the influence of sunlight. 

 It would be folly to dogmatise, and say that coloration of the 

 disc is only accidental, and of no service to the plant, because 

 observation has as yet given no clue to the mystery. It would 

 be far more reasonable to assume that there is a purpose for 

 everything, and endeavour to ascertain what that purpose may 

 be. Why are the majority of brightly coloured species of a 

 soft and fleshy consistency, as in Calloria and Orhilia, and why 

 are the black, or nearly black, species tough and coriaceous, as in 

 Ti/mjMnis and Urnula ? 



The economic uses of the discoid Fungi are limited to but 

 a few species, and these comprised within three or four genera. 

 The Morels are widely known and appreciated, and deserve to 

 stand at the head of the list. There are in all twenty-four 

 species of Morchella, all of which may be assumed to be edible. 

 Eighteen of these are European, two North American, two 

 Asiatic, one common to Eussia and North America, and one 

 confined to the Canaries. Two or three of the European 

 species have a wide distribution, being found also in North 

 America, Australia, Tasmania, and Kashmir. The nine species 

 of Gyromitra are rarer and of less importance. Helvetia, though 

 including forty-five species, contain a large proportion which 



