126 



MOSSES AND FERNS 



CHAP. 



on the sporogonia is not to be assumed. The mucilage slit 

 becomes wider, and beneath it an intercellular space is formed 

 which widens into a cavity whose cells secrete the abundant 



FIG. 65. Anthoceros fusiformis. A. Young plant with single growing point (.r), X8s; 

 B, horizontal section of the growing point of a similar plant, X525; x, the single 

 apical cell; C, similar section of a growing point from an older plant, with pos- 

 sibly more than one initial cell, X2oo; D, a mucilage slit from the ventral side of 

 the thallus, 



mucilage filling it. This mucilage escapes through the clefts 

 and covers the growing point in the same way as that secreted 

 by the glandular hairs in the Jungermanniacese. 



