314 



PART IV. CLASSIFICATION. 



structure and development from the true stomata which are to be 

 found on the sporophyte of Anthoceros and of most Musci, as well 

 as on the sporophyte of the higher plants. 



The SPOROPHYTE, the asexual spore-producing form, is developed 

 from the oospore within the venter of the archegonium (Fig. 196). 

 The oospore divides first into two cells by a transverse wall, the 

 basal u-allj at right angles or obliquely to the long axis of the 



archegonium ; the upper cell, 

 the one next the neck, is 

 termed the epibasal cell, 

 the lower the hypobasal 

 cell. This is followed in 

 some Hepaticse (Marchan- 

 tiaceae, Anthocerotacese) by 

 the formation of two walls, 

 at right angles to the basal 

 wall and to each other, 

 which are known as the 

 quadrant and octant walls, 

 since they respectively seg- 

 ment the oospore into quad- 

 rants and octants of a 

 sphere. In other Hepaticse, 

 and generally in the Musci, 

 the segmentation into oc- 

 tants is confined to the 

 epibasal cell, the hypobasal 

 cell either remaining un- 

 divided, or dividing irregu- 

 larly. With the exception 

 of some of the lower Hepa- 

 ticae (Riccieae), where epi- 

 basal and hypobasal cells 

 alike contribute to the 

 formation of the capsule in 

 which the spores are de- 

 veloped, the epibasal cells 

 alone give rise to the cap- 

 sule. The hypobasal cell gives rise to the foot, which is well- 

 developed in the lower forms of both Hepaticae and Musci, but 

 is rudimentary in the higher. The foot is essentially an em- 



FIG. 196. Funaria hygrometrica. A Develop- 

 ment of the sporogonium (/ /) in the ventral 

 portion (6 I) of the archegonium (longitudinal 

 section x 600). B C Different farther stiiges of 

 development of the sporogonium (/) and of 

 the calyptra (c) ; 7i neck of the archegonium. 

 ( x about 40.) 



