NATURE OF MOSSES. 7 



' archegonium/ consists of a pitcher-shaped cyst, within which 

 there is a single free cell at the base, which is destined, after 

 impregnation, to produce first an embryo and then by con- 

 tinued development a perfect plant like the parent, which 

 either once only or annually through a shorter or longer suc- 

 cession of years gives rise to fruit, consisting of a sporangium 

 filled with spores, destined after germination to go through 

 the same circle of phenomena. In some cases two different 

 kinds of spores are produced, one of which gives rise to the 

 male, the other to the female organs. 



In Mosses, on the contrary, and their allies, the object 

 after germination is to form a more or less filamentous or 

 scale-like stratum, resembling either a little green Lichen or 

 one of the verdant thread-like Confervse, such as Lyngbya mu- 

 ralis, which clothes damp trees or the soil at the base of walls 

 on the northern side, or that which is least exposed to the 

 direct rays of the sun, and, when this is perfected, nodules ap- 

 pear, which by cell formation give rise to the proper plant, 

 whether symmetrical or unsymmetrical, whose office is to pro- 

 duce fruit. On this plant then, either in the same or in dis- 

 tinct individuals, male and female organs are produced (Plate 

 I. fig. 2, 3, 4), resembling more or less closely the antheridia 

 and archegonia of Ferns. In the latter there is a cell at 

 the base analogous to that in the archegonia of Ferns, which 

 is destined to be fertilized by spermatozoids formed in the 

 tissue of the antheridia. 



The result however of fertilization is totally different from 

 that which obtains in Ferns. There a distinct plant was pro- 

 duced from the fertilized cell, the result of germination being 

 a prothallus, and the result of impregnation the true plant; 

 whereas in Mosses and Moss-allies the cell-division of the 

 basal cell of the archegon is a sporangium, or, as it is fre- 



