Ceratiomyxa 15 



and figures of C. sphaerosperma do not show differences greater 

 than those observed in the two varieties mentioned, and appear 

 to be only varietal. 



Subclass II. ENDOSPOREAE 



Spores developed within sporangia, plasmodiocarps, or aethalia. 



Order I. AMAUROCHAETALES 



Capillitium present. Spores violet-brown or purplish gray, 

 ferruginous in Stemonitis axifera and S. flavogenita, colorless in 

 Echinostelium. 



Suborder I. PHYSARIINEAE 



Deposits of lime either in minute granules included in the 

 sporangial wall, in expansions of the capillitium, or in the stalk; 

 or in the form of stellate or lenticular crystals scattered over the 

 sporangial wall. 



Family I. PHYSARACEAE 



Deposits of lime in minute, round granules more or less aggre- 

 gated, included in the sporangial wall and in vesicular expansions 

 of the capillitium called lime-knots, except in Diderma where 

 there are no lime-knots, and in DiacJiea in which the lime is con- 

 fined to the stalk and columella, and is sometimes in the form of 

 rounded nodules. In this family, and also in Family II, Didyniia- 

 ceae, the stalk of the sporangium is developed as an open tube, 

 through which the protoplasm passes to form the young, swelling 

 sporangium; later, the walls of the stalk contract in folds, often 

 enclosing refuse matter (a probable exception in Physarum 

 penetrate) . 



Capillitium a coarse network charged with Hme throughout. 2. Badhamia 

 Capillitium a network of slender threads with vesicular ex- 

 pansions filled with lime-granules (lime-knots). 

 Sporangia combined into a convolute aethalium. 4. Fuugo 



Sporangia single, scattered or aggregated. 



Sporangia subglobose, lenticular, or in the form of 

 plasmodiocarps; capillitium without free hooked 

 branches. 3. Physarum 



Sporangia stalked, shortly cylindrical, hollow, with 



spike-like processes. 5. Physarella 



Plasmodiocarps cylindrical or applanate, branching 

 and anastomosing; capillitium with free hooked 



