April, 1901] 



Kellerman — Mosses. 



103 



the "per-i-che-ti-um " or perichetial scales. This structure, consisting 

 of the delicate reproductive bodies and their conspicuous and surround- 

 ing protecting organs, has been called the " flower " of the mosses. 



The microscopic bodies produced in the antheridia (and called 

 " sper-mat-o-zoids "), and that produced in the archegonia (and called 

 the "o-o-sphere "), are designated by the term "gam-etes;" it is their 

 union that constitutes "fertilization." It can now be understood why 

 this stage of the development of the moss plant, as outlined in the 

 preceding paragraph, is designated by the term " gam-e-to-phyte;" it 

 is the plant (or generation) that produces the gametes. It is in popular 

 language the "moss " plant. 



The fusion of the two gametes results in the production of the 

 sexual spore, called the " o-o-spore ;" it develops at once into the second 



Fig. 2. 



generation, or second stage in the life-cycle of the moss plant, which 

 is called the " spo-ro-phyte." It consists of the seta and capsule; the 

 lower end ("foot") of the seta becomes early embedded and fixed in 

 the tissue of the gametophyte, and from it is derived the nourishment 

 necessary to complete the development of the sporophyte, or the plant 

 that produces the numerous non-sexual spores. This " alternation of 

 generations,"— that is, the alternation of gametophyte and sporophyte, 

 — is not peculiar to Mosses, but occurs also in the Pter-id-o-phy tes and 

 Sper-mat-o-phytes. 



CLASSIFICATION OF THE VEGETABLE KINGDOM. 



I. Thal-lo-phytes; as the Slime-moulds, Bacteria, Common Algae 

 (green Pond-scum, etc.), Marine Algae (" Sea-moss "), Moulds, Mildews, 

 Smuts, Rusts, Mushrooms, Toadstools, Puffballs, etc. 



II. Bry-o-phytes; The Mosses and Liverworts. 



III. Pter-id-o-phy tes; The Ferns, Club-mosses and Horsetails. 



IV. Sper-mat-o-phytes; The Gymnosperms (Pines, etc.) and An- 

 giosperms (Monocotyls and Dicotyls). 



Fig. 2. — The growth or prolonema (/r.) from the spore (5/>.), having rhizoids (>-), and buds (6). 

 from which stems develop. 



