290 



Introduction to Botany. 





mosses perform the same functions as do those of higher 



plants. 



177. Reproduction of Mosses. An examination of the 



apices of moss shoots reveals the fact that archegonia and 



antheridia (Fig. 151) are pro- 

 duced there, in some species 

 both on the same plant, and 

 in others on different plants. 

 The archegonia and anther- 

 idia are small and obscure, 

 and would be overlooked by 

 the casual observer. The wall 

 of the antheridium breaks 

 open at its apex (Fig. 151, B\ 

 and the sperms (s and /) 

 being freed, swim about in 

 the dew or rain which has 

 collected over the plants ; and 

 being attracted by some chem- 

 ical substance secreted within 

 the archegonia (Fig. 151, A) 

 they enter these through their 

 FlG - I 5 I - hollow apical elongations, and 



A, archegonium with egg cell at the base one sperm in each Case f USCS 



of the cavity, and B, antheridium of a i -i 



moss. At j and t are sperms ; these With the egg. 



are seen escaping from the apex of B. Tn e fertilized egg immedi- 

 All highly magnified. After SACHS. 



ately germinates without leav- 

 ing its position in the archegonium, and the rod-shaped 

 embryo, as it elongates, breaks off the narrow upper part 

 of the archegonium and carries it as a sort of cap called the 

 calyptra (Fig. 150 B, c). At the same time the lower part 

 of the embryo pushes its way down into the tissues of the 

 parent plant, from which it continues to draw food until 



