5 S BOTANICAL GAZETTE [january 



Fig. io. — Vertical section of developing air cavities in an archegonial 

 receptacle; X750. 



Fig. ii— Vertical section of an air pore of the thallus; X667. 



Fig. 12— Vertical longitudinal section of a thallus with two archegonial 

 receptacles and one antheridial. 



Fig. 13.— Vertical section of a pore in an antheridial receptacle. 



Fig. 14.— Vertical section of an early stage of an archegonial receptacle; 

 X67. 



Figs. 15-20.— Stages in the development of an air pore of the archegonial 



receptacle. 



Fig. 21. — Surface view of an air pore of the thallus. 



Figs. 22-27.— Stages in the development of the archegonium before the 

 formation of the egg; fig. 25 shows also the origin of a scale and of the invo- 

 lucre (i). 



Fig. 28.— Vertical section of a venter after fertilization; n, nucleus; g, 

 spherical globule; X667. 



Fig. 29.— Vertical section of an archegonium inclosing a young embryo; 



X47°- 



