406 



BOTANICAL GAZETTE 



[DECEMBER 



cells divide transversely (p, p, fig. 8), and soon another division occurs 

 (p, fig. q), by which three cells are formed, a basal cell (b), a stalk 

 cell (s), and a gemma cell (g). The latter continues to divide in the 



Fig. a. — Progressing transverse (p) 

 and longitudinal (/) division of gem- 

 miparous cells; the former producing a 

 basal cell (b), a stalk cell (s), and a 

 gemma cell (g). 



Fig. 10. — Basal cell of p undergoing 

 longitudinal division; w, much further 

 developed and depression deepened; I, 

 young air chamber; /, /, /, shows rela- 

 tion of cupule and air chamber. 



fashion frequently described and figured (cf. also figs. 11, 12, 13), 

 and finally produces the gemma. The stalk cell undergoes no 

 further division, but the basal cell divides longitudinally at least once 

 (p, fig. 11). Later it may undergo repeated division, producing new 



