78 N. H. COWDRY. 



The mitochondria, which are also quite numerous, are fre- 

 quently clumped about the periphery of the vacuoles, but they 

 are never to be found within them, and this is another and very 

 important distinction between mitochondria and bacteria which 

 are phagocytized by Myxomycetes and are segregated and di- 

 gested inside the vacuoles. The heaping up of mitochondria 

 about the vacuoles may be merely a surface tension phenomenon. 

 Their accumulation about the nuclei represented in Figs. I, 3 

 and 4 may also*be due in part to surface tension. It is important 

 to bear in mind that the areas of clear protoplasm are, in their 

 deeper parts, devoid of both mitochondria and vacuoles which 

 become more numerous as we approach the nuclei, and that we 

 may be dealing with nothing more than a heaping up of mi- 

 tochondria in foci of more rapid metabolism. 



Still mor abundant mitochondria are shown in Figs. 4 and 6 

 but the vacuoles are fewer. Different parts of the organism are 

 often separated by irregular, dense and homogeneous septse, 

 not related to capillitium threads, one of which is illustrated. It 

 often happens that stretches of protoplasm separated in this way 

 may exhibit a difference in the intensity of staining, the extent 

 of vacuolation or in the number of mitochondria. 



Fig. 2 of Lycogala epidendrum shows a portion of the active 

 protoplasm of the plasmodium migrating upward through the 

 interstices of the hypothallus to the aethalium where the spores 

 will be formed. The nuclei are still spherical and of about the 

 same size, but contain more distinct and prominent nucleoli. 

 The mitochondria show little tendency toward perinuclear con- 

 densations. The protoplasm appears to be of rather open tex- 

 ture. The hypothallus presents an ill-defined fibrous appearance 

 and is quite devoid of mitochondria and nuclei. 



Spore Formation: 



The early stages in spore formation in Badliamia are illus- 

 trated in Fig. 8. The nuclei, which were so conspicuous in the 

 plasmodium, can no longer be seen with the aid of mitochondrial 

 methods of staining. Their loss of affinity for iron hematoxylin 

 and other basic dyes calls to mind the condition of affairs in 

 oogenesis of certain animals where there is a temporary dis- 



