FUNARIA. 337 



475. L. S. of Capsule (Figs. 81, 82). Select sporo- 

 gonia in which the peristome and operculum are still of 

 a pale yellow colour, cut across the seta near the top, and 

 then cut thin longitudinal sections of the capsule ; also cut 

 a series of transverse sections at different points, for com- 

 parison. 



In a median longitudinal section, note first the seta, 

 expanding above to form the apophysis, which passes 

 gradually into the capsule proper (the "sporangium") 

 which is separated by a constriction (in which lies the 

 annulus) from the operculum. The whole structure is 

 somewhat complex, and a large drawing should be made 

 showing the following details. 



(a) The spore-sac, in a strictly median longitudinal 

 section, is almost U-shaped, but broken through at the 

 base by the lower portion of 



(6) the columella, which also extends upwards into the 

 concave inner portion of the operculum ; outside of the 

 spore-sac, which surrounds the columella, there are two or 

 three layers of cells, forming the inner wall of 



(c) the air-space, which is traversed by filaments 

 (trabeculae) consisting of long narrow cells joined 

 externally to the inner surface of 



(d) the capsule wall (or sporangium wall) ; the latter 

 consists in this region of two or three layers of cells 

 covered by a distinct epidermis the outer layers form 

 compact colourless tissue, while the inner cells are loosely 

 arranged and contain chloroplasts. Below the end of the 

 spore- sac this colourless tissue of the capsule- wall thins 

 out, while the inner green tissue increases in thickness, 

 forming in 



(e) the apophysis a broad zone of spongy green tissue, 

 around the compact central tissue which is continuous 

 below with 



(/) the central strand of the seta. Trace the epidermis 

 downwards to the apophysis, where the green tissue lies 

 directly within it, and note 



(</) the stomata, which will be examined presently in 

 surf ace- view. At the lower end of the spore-sac, where the 

 p. B. 22 



