CRYPTOGAMIA. 415 



algal cell obtains, as a rule, its nourishment in a legitimate, indepen- 

 dent way, the fungal cell extracts it after a more or less parasitic 

 manner. A parasitic life, however, is not uncommon among the 

 Algae. The large Algae (such as Focus] often attain colossal di- 

 mensions and a tree-like form, while the filamentous plants form 

 wavy masses sometimes of considerable length. Those Algae which 

 consist of single cells sometimes possess the power of motion by 

 fine cilice (as in the animal Infusoria), while sometimes they form 

 colonies cohering by the gelatinous substance just mentioned. The 

 reproduction of Algae is effected by both sexual and asexual means ; 

 and these processes bear often a striking resemblance to those 

 which occur in the Fungi. The asexual means consists usually in 

 the separation of some merely vegetative part from the mother 

 plant and in the detachment of gemmce. In the sexual reproduc- 

 tion a variety of processes obtain which will be described when the 

 families in which they occur are treated of. 



The Order CHABACEJS forms a link of connexion between the 

 Algae and the Cormophyta, while on the lower frontier such 

 organisms as Bacteria unite the lowest plants with the lowest 

 animals. 



SUBKI^GDOM II. CRYPTOGAMIA, or FLOWERLESS PLANTS. 



Plants reproduced by spores destitute of an embryo. 



CLASS I. COEMOPHYTA. 



Cryptogamous plants usually provided with stems, leaves, and 

 roots, or their morphological equivalents. 



Under this head is associated a number of vegetable forms which are 

 closely allied to the Phanerogams in the details of their vegetative struc- 

 ture, but which are separated from them in the processes of their sexual 

 reproduction. Even in their reproduction there is to be observed a degree 

 of similarity with the Gymnosperms (a group of Phanerogams), though 

 this is of so remote a character and so different in the steps by which the 

 point of similarity is reached that near affinity cannot be asserted of 

 them. On the other hand, the vegetative organs are morphologically and 

 physiologically of similar value in Cormophytal Cryptogams and Phane- 

 rogams. Just as we have in Phanerogams a scale of degrees in the deve- 

 lopment of the vegetative body, extending from the morphologically perfect 

 down to the cellular plant, in which leaves, stems, and root are repre- 

 sented by aflat thalloid formation (Lemnacece}, so we have in the Cormo- 

 phytal Cryptogams a similar scale, in which the degrees are perhaps 

 more strongly marked. In the Cormophytal Cryptogams the Filices re- 

 present the highest degree in the scale, with stem, root, and leaf perhaps 



