THE PROPAGATION OF PLANTS. 



91 



different cells, and this is never better shown than in the case of the 

 mistletoe and apple, as the former lives on 

 the latter as though it were grafted, and forms 

 one continuous piece of wood (fig. 121). 



We not only obtain the continuation of 

 any particular plant by grafting, but in certain 

 cases we influence its fertility. A pear grafted F"=- "^'-Mi^'i^'o^nd Apple cdis. 

 on a quince becomes fruitful years before it would on its own stock. 

 An apple worked on Paradise stock has the fertility much improved in 

 the young state. Rivers has sought to improve the fertility of the 

 cherry-tree by working it on the mahebeb, and that of the filbert by 

 working it on the Corylus arborescens. 



We propagate our cryptogamic plants in three or four ways. First 

 by spores which produce varieties within certain limits, like the 

 higher plants, as is the case with the spores of the mushroom, which 

 Mr. Smith for the first time has figured in the act of germinating 

 (fig. 122). Any definite variety of fungus may be propagated by the 



Fio. 122 — Mushroom Spores germinating. 



Fig. 123. — By Mycelium. 



mycelium, whereby we secure perpetuation of the individuality of the 

 original (fig. 123). In the case of ferns we constantly secure the 

 multiplication by simple division. In the propagation of plants the 

 seasons should be regarded, and as a rule the period of commencing 

 growth is best adapted for the propagation of plants. 



" Nee tibi tam prudens quisquam persuadeat auctor, 

 Tellurem Borea rigorem spirante moveri. 

 Rura gelntum claudit hiems ; nee semine jacto 

 Concretam patitur radicem affigere terrae." — Virgil, Georg. ii. 



