Mr J. Scott on the Sexuality of the Higher Cryptogams. 195 



spermatozoa and archegonial cells.* I have found, how- 

 ever, that tliis is far from being the case ; for, after numer- 

 ous experiments, the subject of the following remarks is 

 the only one to which I can with certainty assign a cross 

 origin. The history of this plant may be thus briefly 

 told : — I placed thirty macrospores of Selaginella Daniel- 

 siana on the surface of a pot of moist sand ; over these I 

 strewed thickly the microspores of Selaginella Martensii, 

 and then closely covered all with a small bell-glass. In 

 case of differences in the time required for the perfect de- 

 velopment of the male and female organs of the respective 

 species, for some time after the first sowing, I frequently 

 added fresh microspores of the latter species, S. Martensii. 

 Ultimately one of the macrospores produced a germ-plant, 

 all the others proving abortive. The gradual development 

 of this germ-plant I have watched with interest, and I have 

 now the pleasure, through the kindness of Mr M'Nab, of 

 placing it and its parent forms upon the table for the ex- 

 amination of this Society. 



Previous to my noticing the individual and relative char- 

 acteristics of hybrid and parents, there are one or two other 

 points on which I beg to make a few remarks, by way of 

 obviating certain objections which may be advanced against 

 the hybrid nature of my seedling ; they are as follovv^s : — 

 A. Braun Plantarum novarum et minus cognitarum adum- 

 brationes," 1857, Appendix, p. 16) considers that Selaginella 

 Martensii and S. Danielsiana are conspecific ; and taking the 

 former for the normal or typical form of the species, calls it 

 S. Martensii normale ; the latter S. M. compacta. Three 

 other forms, considered by some as distinct species, have 

 also been referred by Braun to S. 3Iartensii under the 

 following names : — S. M. flaccida^ divaricata, and congesta. 



* A single illustration will show the necessity for attending to the period 

 required for the development of the spermatozoa and archegonia in the species 

 tried. Thus, in the closely allied Selaginella denticulata and S. helvetica, the 

 spermatozoa and archegonial cells are developed in the former species ahout 

 six weeks after sowing ; whereas, in the latter species, according to Hof- 

 meister, the microspores lie five months, and the macrospores between six and seven 

 months, before they produce their respective spermatozoa and archegonia. We 

 thus see that here, as elsewhere, in the vegetable kingdom, other points than 

 recognised systematic aflSnities must be attended to in hybridizing. 



