FERN GROWING 83 



of sperms must have been deposited in one or more 

 germs.* 



Illustrations of the parents of these Ferns, in all the 

 experiments, will be found in their proper position in the new 

 edition of " Our Native Ferns," and reference will hereafter 

 be given to their offspring. 



It may be added that in 1879 a repetition of this cross 

 gave identical results. 



EXPERIMENT NO. V. 



In 1883 three varieties oi Aspidium angulare were sown 

 together : in<zquale of Padley, polydactylum of Jones, and 

 variegatum of Moly, half of the mixture by myself, and half 

 by Colonel Jones at the Clifton Zoological Gardens. The 

 variegatum is normal except as regards its variegation, and 

 the incequale has normal pinnae with depauperate pinnules. 

 The seedlings came to maturity in 1887, and, amongst the 

 plants, both Colonel Jones and myself raised an incequale 

 that was both polydactylous and variegated. 



To produce these varieties at once could only be done, 

 either by two different sperms acting on a single cell, or by 

 two cells being crossed on the same prothallus, which, by what 

 the author calls assimilation, may have spread the effects through 

 this prothallus. This would not be requisite if we assume 

 that more than one sperm acted on the same cell. 



The above experiment brought out an interesting fact, viz., 

 that it is possible to transfer variegation in these crosses. 



Moly's variegatum sometimes bdars fronds that are entirely 

 white, and their spores seem as perfect as possible. Major 

 Cowburn and the author sowed a number of pans with spores 

 of this, in the hope of producing plants with white fronds ; 

 neither of us, however, succeeded in raising a single plant. 



* If we assume that two or three germs had each been fertiHsed by only one 

 sperm, there would still be equal proportions of male and female characters. 



