42 MORPHOLOGY OF ANGIOSPERMS 



of gametophytic tissue namehythe reduce'd number of chromo- 

 somes (Fig. 53). With this division, therefore, the history of 

 the male gametophyte begins. This line of demarcation be- 

 tween sporophyte and gametophyte is easy to define, but does 



FIG. 15. Forms of stamens, 1, Calandrinia compressa ; 2, Solanum Lycopersicum ; 3, 

 Galanthus nivalis; 4, Cyclamen europaeum\ 5, Ramondia pyrenaica; 6, 7, Cassia 

 lenitiva ; 8, Pyrola rotundifolia ; 9, Arctostaphylos Uva-ursi ; 10, A. alpina ; 1 J, 

 Vaccinium uliginosum : 12, Pyrola uniflora ; IS, Medinilla (after BAILLON) ; H, 

 Vaccinium Oxycoccus ; 15, Calceolaria Pavonii ; 16, Tozzia alpina ; 17, 18, Sikbaldia 

 procumbens; 19, Galeopsis angustifolia; 20, 21, Erythraea Centaur eum\ 22, 23, Me- 

 lissa officinalis; 2^, 25, Calla palustris; 26, Nyctandra (after BAILLON); 27, 28, 

 Globularia cordifolia; 29, 30, Theobroma Cacao ; 31, Pinguicula vulgaris; 32, 

 Garcinia. From KERNER'S Pflanzenleben. 



not result in so simple a conception of the alternating genera- 

 tions as to begin the gametophyte with the germinating spore, 

 for it involves the simultaneous origin of four gametophytic 

 generations from the mother-cell through an intermediate divi- 

 sion. The claim that the reduction division must be regarded 



