CBYPrOGA3IS 



181 



plant bod}' is very thin and much expanded, and reaches a 

 length of several feet. In most cases the plants are 

 attached by more or less rootlike holdfasts. The often 

 beautiful color is due to the presence of a red pigment, 

 which more or less completely masks the chloropliyll. 



434. Reproduction. — A cluiracteristic method of bearing- 

 spores is ill groups of four (Fig. ^'JSJ^, eacli group result- 

 ing from the division of the contents of 

 an original mother cell. Such spores are 

 termed tetraspores. They are briglit red 

 bodies without cell walls, and being un- 

 provided with cilia, are dependent upon 

 water currents for dissemination. 



435. Reproduction, with fusion of the 

 reproductive cells, may be illustrated by 

 the case of Nemalion ; this being taken 

 as a siinjde instance of a process which 



« in some members 



o ° a the o'roui) becomes 

 liighly complicated. 

 The rejiroductive cells of Nemalion are 

 pollinoids, naked spherical cells pro- 

 duced singly in rounded antlieridia 

 (Fig. 300, a), and 

 differing from an- 

 therozoids only in 

 being un ciliated; 

 and egij celh U irnied 

 witliin elongated 

 cells termed carpo- 

 gonia (Fig. 300, c). 



300. NBiaalion: yl.sliowing tlie carpngonium (o), ^ '"^ ^'SE OCCUpies 

 trichogyne (0 Willi pollinoids near, ami tlie enlarged Ijasal 

 antlieridia (a); B, after fertilization, tlie . . , 

 carpogoniuni beginning to lirancli; C. tlie portion Ot tllO car- 

 nearly niatvire spore-bearing body (cystu- pogonium, the hair- 

 carp, c//).—Thuret. ,.,' , ., J 



like extremity oi 

 whicli is known as the tnchofiyne (t). Several pollinoids, 

 brought by circulation of the water, may adhere to the 



of 21)1). fclnspoits (7) 

 in a tiliiuent 

 of Pnlysiplio- 

 nia. 



