INTKODUCTION TO CEYPTOGAMIC BOTANY. 



437 



fully observed the morphosis of the elaters.* The sporangia 

 are at first filled with a mass of oblong cells, some of which 

 are broader than the others. The protoplasm of the broader 

 contracts into a number of separate masses. These occasion- 

 ally are divided again longitudinally, so as to form a double 

 row, and in either case each becomes a mother cell. The 

 narrower, on the contrary, produce the elaters (Fig. 91, b). 



rig. 91. 



a. Fruit of Cronida paradoxa. From a sketch in the Hookerian 

 Herbarium. 

 6. End of elater oi Marchantia polymorpha. 



c. One of the broad cells with the endochrome breaking up into 

 mother cells, after Henfrey. 



d. Section of Archegonium of ditto, with embryo cell, and the proper 

 invrolucre at the base, after Hofmeister. This, in situ, is dependent. 



e. Antheridium of Targionia, after Thuret. 

 /. Spermatozoids of the same. 



g. Sporangium of M. polymorpha, and proper envelope.f (See 



Fig. 92, d.) 



All more or less magnified. 



* Linn. Trans., vol. xxi., p. 103. 



t This is said to be formed from the pistillidium, by Henfrey, 1. c. 

 The pistillidium or archegonium, however, is adherent to the base of 

 the peduncle when the sporangium is protruded. 



