444 



STRUCTURE AND LIFE HISTORIES 



397. Annual Bulbs. At the base of an old flowering 

 bulb, and in the axil of one of the bud-scales, there de- 



FIG. 329. Diagram of life-cycle of an angiosperm (Alisma Plantago- 

 aquatica). 9, female gametophyte (embryo-sac) ; 8a and 90, male gameto- 

 phyte (pollen-grain). (After J. H. Schaffner.) 



velops each year an annual bulb, which attains full size 

 about April, and begins in May to form the bud for the 

 leaves and flowers of next spring. 



