in 



MARCHANTIE^ 



51 



irregular. 



The separation of the central cells from the wall 

 is exactly as in Ricda, and the lower segments do not take 

 any part in the forma'tion of the sperm cells, but remain as 

 the basal part of the wall. In Fimbriaria the top of the 

 antheridium is prolonged as in Ricda, but in Marduintia this 

 is not the case. The wall cells, as the antheridium approaches 

 maturity, are often much compressed, but in Targionia hypopJiylla, 



Fig. 15. — Fimbriaria Calijornica (Hampe). A, Longitudinal section of a fully-developed male re- 

 ceptacle, x8 ; B, longitudinal section of a nearly ripe antheridium, Xioo ; C, young sperm cells, 

 x6oo; D, spermatozoids, X 1200. 



where Leitgeb ^ states that this compression is so great that 

 the cells appear like a simple membrane, 1 found that, so 

 far from this being the case, the cells were extraordinarily 

 large and distinct, and filled the whole space between the body 

 of the antheridium and the wall of the cavity, which in 

 Leitgeb's figures "^ is represented as empty. The antheridium 

 becomes sunk in the thallus precisely as in Ricda. The sperm 

 cells are nearly cubical and the spermatozoid is formed in the 



^ Leitgeb (7), vol. vi. PI. X. Fig. 12. 



" Leitgeb, I.e. 



