2l8 



i.e. to produce young by mere asexual budding from the 

 prothallus — have yielded in all native species plenty of 

 good forms, although the exotics, with the exception 

 of N. molle, have done but little in that way. Osmunda 

 regalis has given both crested and fine-cut types probably 

 capable of introduction into the several exotic species, 

 since they are certainly closely allied. All these possibilities 

 being assumed, the next question, and a vital one, is — How 

 are they to be attacked ? and this is a very simple matter. 

 The crossing of Ferns, unfortunately, cannot as yet 

 be systematically done, as with flowers, owing to the 

 microscopic nature of the reproductive process ; but 

 numerous successful attempts prove that if the spores 

 of the two parental forms be sown together in one pan, 

 there is the chance of the antherozoids or fertilising 

 organisms of one prothallus being conveyed either by 

 water or insect agency to another, and thus effecting a 

 cross. Hence success would doubtless crown the efforts 

 of the Fern spore sower who, when sowing his exotics, 

 persistently scattered the spores of likely British partners, 

 on the lines above indicated, among those of the exotic. 

 Or, in view of the fact that spores vary considerably in the 

 time occupied in producing the prothallus, and eventually 

 the Fern proper, he might sow separately and subsequently 

 associate by pricking out patches of each and replanting 

 in very close juxtaposition. This we believe was the way 

 P. Schneideri was obtained. On the other hand, there is 

 considerable range of time between the maturing of Fern 

 prothalli, even in the same sowing, so that success might 

 well be obtained in the simpler way of sowing together. 

 In any case, nothing is lost by the attempt, since with 

 judicious selection of good forms a crop of the parental 

 types is obtained, and is worth having, even if the wished- 

 for conjunction fails. 



Chas. T. Druery, V.M.H., F.L.S. 



