1904} GARBER: RICCIOCARPUS NATANS 163 
all purposes except to show a series of stages in a single section, 
in which case the sections should be parallel to the furrow. 
Delafield's haematoxylin or Heidenhain’s iron-alum haema- 
toxylin proved excellent for young stages of the sex organs, and 
the latter stain was especially good for older stages of the spo- 
rophyte. Flemming’s safranin gentian violet combination was 
most satisfactory for nearly mature archegonia and the process 
of fertilization. 
Fig. 1.—a and ¢, plants injured by insects, 
the apical cells growing independent branches ; 
| 6, single branch of soil plant like fg. 2+ a-i, Suc- 
@ 4 cessive stages in the growth of fruiting plants. 
| Fic. 2.—A rosette growing on the soil. 
| Fic. 3.—Vegetative water plants in autumn. 
em 
THE THALLUS. 
Ks @ ah | Ricciocarpus natans. 
3 | 
The common floating form of Ricciocarpus is so familiar, and 
has been so well described by Bischoff (13) and others, that no 
further description of external appearance scems necessary. A 
series of stages in the development of the floating form is shown 
in fig. I (a-t). 
