1 88 STUDIES IN FOSSIL BOTANY 



the megaspore and prothallus from a fructification, 

 provisionally named Mazocarpon, distinguished by the 



Fig. 77. — Lejiidostrobus Vclthehnianus. Megaspore in section, filled with prothallus, 

 which protrudes somewhat through the opening of the megaspore-wall. X 50. S. 

 Coll. 912. R. S. 



fact that the megaspores in the sporangium are em- 

 bedded in a massive parenchymatous tissue. In other 

 specimens traces of the archegonia are recognisable. M. 



Fig. 78.— Mazocarpon, Benson in MS. Isolated megaspore filled with prothallus. 

 X about 35. From a photograph by Mr. W. Tarns. S. Coll. 1756. 



Renault found megaspores of a Lepidostrobus in which 

 the prothalloid tissue contains flask-shaped cavities 

 strongly suggestive of archegonia. 



There is thus every reason to believe that the mode 



