408 SYSTEMATIC BOTANY. 



SUBKINGDOM H. CRYPTOGAMIA, or FLOWERLESS PLANTS*. 

 GENERAL MORPHOLOGY. 



Introductory Remarks. The division of the Vegetable Kingdom 

 into Phanerogamia and Cryptogamia is based on the mode of re- 

 production. It has been seen that in the Phanerogamia the plant 

 accomplishes this by the formation of a seed of which the essential 

 part is the embryo. In the Cryptogams, though the processes by 

 which it is arrived at differ widely among themselves, it will yet be 

 found that reproduction is bound up invariably with the formation of 

 spores destitute of an embryo, and often consisting of simple cells. 

 At the same time there exists throughout the whole Vegetable 

 Kingdom, in Phanerogams and Cryptogams alike, another mode of 

 reproduction called vegetative, which is entirely independent of 

 sexuality, and which usually consists in the mere separation of a 

 part of the mother plant. 



The Cryptogamia are divided into two great groups characterized 

 by difference in the structure of their vegetative organs. The 

 higher group, called Cormophyto, composed of the .Ferns and 

 their allies with the Mosses and their allies, resemble the Phanero- 

 gams in the possession of an axis or stem bearing leaves. The 

 lower group, or Tliallopliyta, comprising the Algae, Fungi, and 

 Lichens, presents in its vegetative structure no clearly marked 

 distinction between root, stem, and leaf ; the plant is composed of 

 a tliallus, formed by simple cellular tissue, sometimes in its shape 

 resembling a leaf, sometimes a stem, and sometimes a root. The 

 simplest plants of this class consist of single cells. Although in 

 general the distinction between Cormophyte and Thallophyte is 

 easily recognized, certain families on both sides possess so close an 

 affinity to each other, that no sharp line of demarcation can be 

 drawn between them. A similar difficulty is experienced on the 

 lower frontier the much disputed borderland between the Animal 

 and Vegetable Kingdoms. 



Cormophyta, or Cormophytal Cryptogams. The Cormophyta, 

 as already mentioned, consist of the .Ferns and their allies, 



[* The sections relating to the Cryptogamia have been revised and in part 

 rewritten by Mr. George Murray, of the Botanical Department, British 

 Museum. Although, for uniformity's sake, the account of the Cryptogams is 

 given in this place, yet the student will be unable to understand the anatomy 

 and physiology of these plants without having previously mastered the contents 

 of the subsequent sections relating to Anatomy and Physiology. ED.] 



