ANGIOSPERMS 



225 



that the anther comes to contain only two spore cham- 

 bers (Fig. 212). These two spore chambers are plainly 



FIG. 212. Cross-section of a mature anther of a lily, much larger than that shown 

 in Fig. 211, showing the two chambers formed by the four sporangia, and also 

 the region of opening (). 



A C 



FIG. 213. Anthers opening by terminal pores: A, Solarium; B, Arbutus; C 

 Vactinium. A and B, after ENGLER and PRANTL; C, after KEENER 



