FERN GROWING 



19 



the example of the cruciate hybrid of Aspidium aculeatum 

 that it is a marked copy of the cruciate form of A. angulare, 

 one of the parents selected with the object of obtaining a 



cruciate P. aculeatum. Instead of the usual gradual process, 

 the form was obtained at once.* This applies equally in 

 the case of the polydactylous forms of A. angulare (see Figs. 



* A further inference that a number of sperms are employed in the impregnation 

 of a cell. 



