92 N. H. COWDRY. 



EXPLANATION OF PLATE II. 



FIG. 6. Enteridium rozeanurn fixed in Regaud's fluid and stained by the Benda 

 method, mitochondria blue-black and ground substance pink. Another septum 

 is shown at the side. The mitochondria occur in distinct clumps sometimes about 

 the nuclei. The apparent differences in the staining reactions of the mitochondria 

 simply indicate depth in the preparation. 



FIG. 7. Fuligo septica fixed in Regaud's fluid and stained with iron hematoxylin, 

 mitochondria blue-black and ground substance gray. Immature spore with a 

 faint nucleus and conspicuous mitochondria. 



FIG. 8. Badhamia - , fixed and stained in the same way. It shows the 



first stages in spore formation. The nuclei are indistinct; the mitochondria show 

 progressive clumping and the spore membranes are gradually formed. 



FIG. 9. Fuligo septica, same fixation and stain. More mature spores of smaller 

 size, without a distinct cell membrane, with strongly stained nuclei and more rod- 

 like mitochondria. The mitochondria often closely approximate to the nucleus. 

 The ground substance is more homogeneous than in the preceding stage and more 

 deeply stained. 



FIG. 10. Fuligo septica fixed and stained in the same way showing rather 

 later stages in spore formation than Figs. 7 and 8. The spores are surrounded 

 with a definite membrane. They have faintly staining nuclei and spherical 

 mitochondria. One of them is rather more advanced. 



FIG. ii. Enteridium rozeanum same fixation and stain. Quite advanced spores 

 with definite capsules. The nuclei are faintly stained and the mitochondria 

 spherical and in one case clumped near the nucleus. 



FIG. 12. Arcyria denudata fixed in Regaud's fluid and stained with fuchsin 

 and methyl green. The mitochondria are crimson against a greenish background. 

 One cell not finally divided containing three nuclei and two others each containing 

 a mass of material in a vacuole. The material consists of a basophilic part, staining 

 green, definitely delimited in the form of spherules, and of a more irregular acido- 

 philic mass staining red. 



