^5 



t 



plants, he regai'ds tjie tetraspore-producing plant as a 

 "fac\iltative gaj/ietophyte" , which is a resx'lt of a process 

 of diff erentia.tion similar to that v/hich produced dioecism 

 in many of the Archegoniates . The tetraspores he consid- 

 ers analogous to the gemmae of certain liverv/orts . Admit- 

 ting the possibility that a nxuaerical reduction of the 

 chromosomes may take place in the tetrasporangivim, he ex- 

 presses the opinion that the numtier of chromosomes is not 

 the final test of alternation of generations, "Ich ver- 

 mvite, die vergleichende Untersuchiing des ganzen Entvvick- 

 elungsganges ftUirt eher ziun Ziel, oder aher die Kombination 

 header Llethoden" ('05, p. 273). 



The v.'ork of "Wolfe on JHemalion multif idum (»04), in 

 which he found a nujnerical reduction of chromosomes just 

 previous to the production of carpospores, furnished a 

 cytological analogy betv/een tiie cystocarp of the Rhodophy- 

 ceae and the sporogonium of the Bryophytes, and strength- 

 ened the position of OLTl'JUTiTS . 



YAI'JMTOUCKI ('Oeb), after a very complete cytological 

 study of Polysiphonia violace^, reached the following con- 

 clusion: "The sexual plants and the tetrasporic plants pre- 

 sent the t\.o distinct phases of an antithetic alternation 

 of generations, with the cystocarp a peirt of the sporophyt- 

 ic phase" (p. 433). This conclusion is based on the dis- 



