BBTOPHTTA. 



185 



masses of cells in small cups 4 to 6 millimetres (i inch) in 

 diameter {S and O, Fig. 101). They are in reality hairs 

 (trichomes) whose upper cells have repeatedly divided so 

 as to form flattish masses. When these fall off they grow 

 directly into new plants. 



388. The antherids of Liverworts are more or less globu- 

 lar, stalked bodies (Fig. 102, C), usually immersed in little 

 depressions in the plant-body. They are to be regarded as 

 hairs (trichomes) whose end cells have become greatly in- 



Fio. 102. — A, a portion of Common Liverwort (Marchantia polymorpha) with 

 two male branches, hu, in which antherids are borne; C, an antherid, magniiied; 

 D, two antherozoids, greatly magnified. 



creased in number. There is an outer layer of cells sur- 

 rounding a great number of interior thin-walled cells, the 

 sperm-cells, each of which contains an antherozoid. 



In the Common Liverwort (Marchantia polymorpha) the 

 antherids are produced in the broadly expanded discs of 

 special branches (Fig. 102, A). The antherozoids are spiral 

 threads of protoplasm, each provided with two cilia (Fig. 

 102, D). 



389. The female organ of Liverworts is called an arche- 



