Mr J. Scott on the Sexuality of the Higher Cri/j)togams. 199 



general imbued with an equal degree of the vegetative 

 force, so that both forks being developed alike, the plants 

 thereby assume a dwarf, compact, bushy habit. In the 

 male parent — 8. Martensii — on the other hand, the right 

 and left forks of the terminal bud are alternately more 

 vigorously developed, so as to give rise to an apparently 

 principal axis, or leading shoot, with a right and left series 

 of branches, and a lax, somewhat spreading habit to the 

 plants. Secondly, In the form of the leaves, and their 

 somewhat laxrachidal disposition, the hybrid exhibits more 

 affinity with the male than the female parent, the only 

 difference being a decreased size. In the denser cellular 

 structure of these organs, however, and likew^ise in the 

 deep lustrous green, with the brownish-tinted stems, the 

 hybrid again approaches the female parent. In the form 

 of the stipuliform leaves and bracteas, it differs from either 

 parent, and here approaches another of the forms which 

 Braun has referred to the S. Martensii, viz., S. M. congesta. 

 Thirdly, In respect to the characteristics of the organs 

 of fructification, there is a great similarity in the three 

 forms, those of the hybrid being the smallest. There is 

 one point, however, in connection with them, worthy of 

 a passing notice, namely, the relatively great variability in 

 the sizes of the microspores of the hybrid — a high per- 

 centage of w^hich are badly developed — as compared with 

 those of the parents ; while the macrospores, though smaller 

 than those of the latter, present in general very trifling 

 relative difierences, and so far as I can judge, until I have 

 time to test their germinative capabilities, perfectly de- 

 veloped. We have here a curious and interesting — real or 

 apparent — analogy, w^ith that which occurs in the phenomena 

 of sterilisation in the hybridisation of the higher plants. 

 Hybridists have shown, that in the latter class of plants, 

 the pollen is more susceptible to the sterilising action 

 than the ovules, and that in general, perhaps invariably, 

 as has been maintained, we find that if the anther-cases 

 contain a few grains of perfectly developed pollen, the 

 ovaries also will contain a higher percentage of ovules 

 capable of fertilisation.* 



*• I believe au exception, of wliicli I will satisfy myself at tlie apprbacLiiig 



