INTRODUCTION TO CRYPTOGAMIC BOTANY. 81 



cuticle, as Asteroma Moscb. It is true, our difficulties of defini- 

 tion have increased; and if Lichens are to be considered as of 

 equal dignity with Fungi, both belonging to one large group, 

 there is a necessity for giving that group a distinctive name. In 

 such matters, systematic effect, or neatness of character, is not 

 to be studied, but the real affinities of plants ; and if a closely 

 allied group be separated too acutely, the affinities will some- 

 times vanish from the view. I shall therefore, at all risks, con- 

 sider Algals, or Hydrophytes, as forming the first grand group; 

 and for the second, propose the name of Mycetals, comprising 

 the two received alliances of Fungals and Lichens. 

 The Thallogens will then stand thus : 



A. Algales. Cellular flowerless plants, for the most part 

 without any proper roots or mycelium, living, with rare ex- 

 ceptions, entirely in water, and imbibing nutriment by their 

 whole surface, from the medium in which they grow. 



B. Mycetales. Cellular flowerless plants, at first, fur- 

 nished with a mycelium, very rarely immersed, deriving nutri- 

 ment from the matrix, or from the surrounding air. 



a. Fungales. Hysterophytal or Epiphytal Mycetals, deri- 

 ving nutriment , by means of a mycelium, from the matrix, 

 never producing from their component threads, green bodies 

 resembling chlorophyll (gonidia). 



b. Lichenales. Aerial Mycetals, deriving, for the most part, 

 nutriment from the surrounding media ; producing, from the 

 component threads of their thallus, abundant gonidia. 



„■ Deriving nutriment from 



J the water in which they 



o are submerged. 



■< 



01 



O 



a 



Deriving nutriment from 

 the matrix, or the sur- 

 rounding air ; mycelium 

 more or less evident. 



«• Hysterophytal or Epi- 



■e phytal :, nourished by the 



S matrix, never producing 



*( gonidia. 



"3 Aerial; nourished by air 

 § and not by the matrix, 

 •S producing gonidia. 



