94 N - H. CO\VDRY. 



EXPLANATION OF PLATE III. 



FIG. 13. Hemitrichia clavata fixed in Regaud's fluid and stained with iron 

 hematoxylin. The mitochondria are blue-black and can with difficulty be dis- 

 tinguished from the granulated ground substance. Plasmodium, within the 

 sporangium, showing an early stage in the formation of the capillitium. The 

 spirals are beginning to appear. 



FIG. 14. Arcyria denudata fixed and stained in the same way. These cells are 

 in the stalk, next the envelope. They will apparently take no part in spore forma- 

 tion. They show indications of cytolysis and contain but few mitochondria. 



FIG. 15. Hemitrichia vesparium fixed and stained in the same way. Spores 

 and cross and longitudinal sections of capillitium. 



FIG. 16. Hemitrichia vesparium, same fixation and stain. A portion of the 

 plasmodium flowing between the meshwork of the hypothallus. The mitochondria 

 are elongated in the direction of movement. There is also a faint striation in the 

 ground substance in the same direction. Some of the nuclei have well marked 

 nucleoli. 



FIG. 17. Arcyria denudata fixed in Regaud's fluid and stained with fuchsin 

 and methyl green. The mitochondria are crimson. There are two immature 

 spores which apparently contain a comparatively large amount of golden yellow 

 pigment. The terminal enlargement of the capillitial thread also contains a series 

 of granulations staining just as the mitochondria do. 



FIG. 1 8. Hemitrichia clavata fixed in Regaud's fluid and stained with iron 

 hematoxylin showing also internal granulation. 



FIG. 19. Hemitrichia clavata fixed and stained in the same way. Plasmodium 

 with cross section of capillitial thread and two types of nuclei, the smaller ones 

 staining darkly and the larger ones lightly. 



