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Commercial Gardening 



life-history of the Fern, and the mystery was one no longer. Detaching 

 one of these scales from the soil, reversing it, and studying it under a 

 good lens, we find it to be a very wonderful structure indeed. Dotted 

 about profusely among the tuft of root hairs we see a number of roundish 

 pimple-like growths (fig. 308 an): and farther up, close to the indentation 

 of the heart-shaped prothallus, we shall see a little close-set cluster of 

 teat-like bodies (fig. 308 ar). Beneath these we may see that the body of 

 the prothallus is considerably thickened, and dissection would show that 

 at the base of each of these teat-like bodies a round incipient seed was 

 embedded. Assuming, then, as we shall be justified in doing, that these 

 teat-like bodies represent the stigmas in flowering plants, and deducing 

 therefrom that the round pimples should represent the male or pollen 

 element, we see at once that the simple one-celled spore shed from the 



Fig. 308. Underside of 

 Prothallus of Fern 



ap, Apex; r, rhizoids; an 

 autheridia; ar, archegonia 

 (magnified). 



Fig. 309. A, Archegonium ejecting mucilage (in); o, 

 oosphere. B, Antheridium ejecting antherozoids. pr, 

 Prothallium (highly magnified). 



parent fern has managed to construct a very complete apparatus for the 

 performance of the reproductive function. The only remaining question 

 is: How is it done? If, while the prothallus is so reversed, we flood 

 it with tepid water, we may, if we are very fortunate, see some of the 

 round pimple-like bodies (antheridia) burst, and from them will be sent 

 a considerable number of extremely minute ciliated bodies (fig. 309B) 

 (antherozoids), which commence to swim actively about in the water 

 (normally existing in the form of a dewdrop), actually steering them- 

 selves definitely towards the teat-like bodies (archegonia) the special cells 

 or oospores at the bases of which it is their province to fertilize, since 

 each contains, as does a pollen grain, the male potency essential thereto. 

 Arrived at the archegonia, they find their way to the incipient seeds 

 (oospores) at the base of the hollow they have traversed, and from that 

 moment the fern " seed " begins to develop by cellular multiplication. Ere 

 long a little frond rises through the indented parts of the heart-shaped 

 prothallus (fig. 307), a little root (r) descends, the fleshy prothallus acting 

 for a time as foster mother, and in this way the young Fern is fairly 

 launched in life after, as we have seen, a very wonderful pre-natal career. 



