228 



MORPHOLOGY. 



a large cavity. Within each cavity there is an oval or ellip 

 tical body, supported from the base of the cavity on a short 

 stalls. This is an antheridium, and one of them is shown still 

 more enlarged in fig. 259. This shows the structure of the 

 antheridium, and that there are within several angular areas, 

 which are divided by numerous straight cross-lines into countless 

 tiny cuboidal cells, the sperm moiher cells. Each of these, as 

 stated in the former chapter, changes into a swiftly moving body 

 resembling a serpent with two long lashes attached to its tail. 



485. The way in which one of these sperm mother cells chani^^es into this 

 spermatozoid is verj- curious. We first note that a coiled spiral bod)- is appear- 



Fig. 259. 



Section of antheridium of mar- 

 chanfia. showing the groups of 

 sperm mother cells. 



I ij:. 200. 

 Spermatozoids of marchantia, 

 uncoiling and one extended, show- 

 ing tlie two cilia. 



ini; within the thin wall of the cell, one end of the coil larijer than the other. 

 The other eml terminates in a slender hair-like outgrowth with a delicate vesi- 

 cle attached to its free end. This vesicle becomes more and more extended 

 until it finally breaks and forms two long lashes which are clubbed at their 

 free ends as shown in fif^. 260. 



486. Archegonial plants. — In fig. 261 we see one of the 

 fetnale plants of marchantia. Upon this there are also very 

 curious structures, which remind one of miniature unibrellas. 

 The general plan of the archegonial receptacle (or female 



