THE AI.GM. 



93 



tilized carpogonium and envelops it. The pericarp and 

 carpogonium together constitute a spore fruit. This spore 

 fruit preserves the life of the plant until the following 

 season. Then, under favorable conditions, a number of 

 flagellated zoospores are formed and liberated, which, after 



FIG. 51. A, part of a fertile thallus of Coleochsete pulvinata, showing the 

 aiitheridia, an, and the oogonia or carpogonia, og, in the process of for- 

 mation. (X 350.) B, ripe oogonium in its rind. C, germinating fructi- 

 fications of C. pulvinata, in the cells of which the swarm spores are formed. 

 D, swarm spores. (B-D X 280.) (From Goebel, after Pringsheim.) 



a period of activity, develop by the asexual process into 

 new plants. The spore fruit is the sporophyte ; the plant 

 itself is the gametophyte. 



References for Reading. Goebel's " Classification of Plants," pp. 

 46-48 ; Bennett and Murray's " Cryptogamic Botany," pp. 220-222 ; 

 Vines' "Text-Book of Botany," pp. 249, 250; Bower's "Practical 

 Botany," pp. 419, 420. 



The Conjugatae. The sexual reproduction in this class 

 is by the formation of zygospores by the conjugation of 

 cells that are apparently just alike, i.e., it is isogamous. 

 The asexual reproduction is by the transverse fission of 



