384 



MOSSES AND FERNS 



CHAP. 



not seen at all, and the origin of the young sporophyte was un- 

 mistakably non-sexual. Prothallia, arising directly from the 

 leaf, or from the sporangial receptacle, were found to be a com- 

 mon phenomenon in the same species. 



THE SCHIZ^ACE^: (Diels (i)) 



The Schizseaceae include about sixty species belonging to 

 five genera. The very characteristic sporangia have a terminal 

 annulus, which forms a sort of crown at the apex. Some of 

 them, like Schiscea pusilla and Trochopteris elegans, are very 



A - B. O. 



FIG. 222. A, Prothallium of Aneimia Phyllitidis, Xi8o; B, female; C, male, prothallia 

 of Scliizaea pusilla, Xso (A after Bauke, B, C, after Britton & Taylor.) 



small and delicate plants. In the largest species of Lygo- 

 dium the slender twining fronds may reach a great length. Ac- 

 cording to Hooker (2), the New Zealand species L. articu- 

 latum, may reach a length of 50 100 feet. 



The Garnet ophyte 



According to Bauke (2), the prothallium in Lygodium, 

 Aneimia, and Mohria is much like that of the Polypodiacese, 

 except that in the two latter genera (Fig. 222), the growing 

 point is at one side. The spores are tetrahedral, and contain 

 no chlorophyll until after germination has begun. The germ- 



