270 



REPRODUCTION OF MARCHANTIA 



and the distribution of the rhizoids and ventral plates are essen- 

 tially as in Ricciocarpus. 



Marchantia, as in many of the liverworts and some mosses, 

 multiplies extensively by means of buds or gemmae. They are 

 borne in cup-shaped receptacles and consist of small lense-shaped 

 masses of cells which are freed from the thallus by the swelling 

 of the mucilage secreted by glandular hairs growing among them 

 (Fig. 189). These minute bodies grow directly into new plants 

 and so serve to rapidly multiply the plant. 



Fig. 190. Thallus of Marchantia bearing several erect branches with 

 lobed or umbrella-like tops. The archegonia are situated on the underside 

 of the umbrella, between the lobes, a, the early appearance of a branch, 

 in which condition fertilization is effected. 



The reproductive organs appear upon different plants which 

 may therefore be distinguished as antheridial or male plants and 

 archegonial as female plants (Figs. 186, 190). Such a distribu- 

 tion of the sexual organs is termed dioecious, meaning in two 

 households, whereas Ricciocarpus and others are said to be mon- 

 oecious, because the sexual organs are developed upon the same 



