85 



similar to that described in Kaulfussia. As in Osnianda there 

 are lateral lobes which are especially marked in G. laevigata 

 (PI. X, Fig. 59 — 61). These arise alternately right and left of the 

 growing point and are foimed by an increased growth in the 

 marginal cells resulting in the projection of the young lobes. 

 The latter very soon show a distinct two-sided apical cell (PI. X, 

 Fig. 61), but this is soon lost and finally the growth appears 

 to be very irregular. Rhizoids are produced in great numbers 

 from the midrib. They are stout and rigid, and the walls 

 become very dark in color. 



There is always present in the older parts of the prothallium 

 an endophytic fungus very similar to that described in Kaal- 

 fussia. This does not seem to differ much from the endophyte 

 that infests the Ophioglossacae. A similar endophyte, as has 

 also been stated, occurs in several Marattiaceae and I have 

 also found it in Osmunda. As this is also the case in many 

 species at least of Lijcopodiwn, it is highly probable that 

 further research among the ferns will show that this endo- 

 phytic fungus is much commoner than has been supposed. 

 The irregular branching hyphae are undivided for the most 

 part, and in the younger portions of the prothallium they 

 usually show plainly more or less constriction where they 

 pierce the cell wall. Except in the oldest cells of the prothal- 

 lium, the nucleus remains evident, but the chromatophores and 

 starch become disorganized and finally disappear. 



The fungus agrees in all respects with that recently described 

 by the writer for Ophioglossum. The oogonium-like enlargements 

 of the hyphae are less frequent than Avas observed in Ophio- 

 glossiun, but otherwise the fungus is very similar. In some cases 

 small round bodies, resembling those seen in these enlarged 

 vesicles, were seen free in the cells of the host, and may have 

 been discharged from the vesicles. Whether or not these are 

 reproductive cells, possibly zoospores, remains to be seen. 

 Except for slight differences in size the endophyte seems to be 

 the same in all species of GleicJienia. 



