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themselves in the same way, and had to be cut out as soon 

 as recognisable. Finally, however, the crop of prothalli 

 still left showed a new type of primary leaf, and the end 

 result was no less than three hundred plants of the type 

 required, all true and characteristic. The associated 

 "rogues" were thus seen to have arisen from the spores 

 of the ferns surrounding the rarity, upon whose fronds they 

 had scattered their spores with their accustomed liberality, 

 the two kinds being thus sown together. 



The lesson taught by this is that it is well to gather the 

 spores of a good form as soon as they are ripe, thus pre- 

 cluding as far as possible that peppering of other spores, 

 which inevitably happens later in the season when the 

 neighbouring ferns are all shedding them freely and 

 scattering them in all directions. Our own plan is to 

 watch the plant we desire to deal with, and as soon as the 

 little spore pods or sporangia turn brown or almost black, 

 we cut off a fertile pinna and lay it back downward upon a 

 glass slip. In a few hours this sHp, when examined under 

 a microscope or a strong lens, will be found covered with a 

 possibly profuse crop of spores, each little pod having burst 

 and scattered its score or two of tiny reproductive bodies 

 over the field of view. Under the circumstances indicated 

 above, these will probably all be of the kind desired. We 

 then sow them very thinly on the surface of scalded soil in 

 small pots or pans, cover these with glass, and place them 

 in a Wardian case or elsewhere where plenty of light is 

 available without direct sunshine. A good plan, when 

 several sowings are concerned, is to bed these pots up to 

 their rims in cocoanut fibre in a larger pan, covering this 

 pan with one sheet of glass. The subsequent watering can 

 then be effected by soaking the fibre from time to time, 

 thus precluding the risk of disturbing the germinating 

 spores, which should be left severely alone. Care must 

 be taken to place the pan where there is no risk of intrusive 

 worms, since these would upset the whole arrangement. 



