American Species of Marchantia. 



305 



the species a delicate pellucid thallus with indistinct areolae but 

 with large pores, the thallus in M. chenopoda being thick and 



Fig. 19. Marchantia chenopoda L. 



Epidermal structures of thallus, x 225. A, B. Pores, surface view. 

 C-G. Pores, cross-section. H-K. Pores, inner view. L. Slime cell, 

 cross-section. A, C, H-J. Guatemala, Cook & Griggs 83. B, D, E, K, L. 

 Jamaica, W. R. Maxon 405. F, G. Peru, Cook & Gilbert 755. 



opaque with distinct areolae and small pores. He states further 

 that the female receptacles are depressed-semiglobose, excentric 

 and almost entire, the five lobes present being very short, thick, 



