MYXOGASTRES 



533 



Speedwell (Veronica}. The galls contain numerous spore- 

 balls, each enclosed in a delicate membrane, and consisting 

 of a single layer of elliptical spores enclosing a central cavity. 

 The individual spores measure 8-9 X 4-4*5 /*. 



Tetramyxa parasitica -(Goeb.) forms little swellings on 

 stalks, leaves, and flowers of Ruppia rostellata. The multi- 

 nucleate plasmodium breaks up into small portions, each con- 

 taining a nucleus. These portions afterwards divide into four 

 spores, each containing a nucleus. The four spores remain 

 joined together, enclosed in a delicate membrane. 



Spumaria alba (D C.) sometimes proves indirectly injuri- 



FIG. 161 .Fuligo varians. The plasmodium 

 has crept over the soil in a plant-pot, and 



formed its mass of spores, which are covered 

 with a yellow crust of lime. 



Reduced: 



ous ; its plasmodium often creeps up the stems of living 

 grasses, and forms spore-masses up to 2-3 inches in length 

 and an inch in diameter. These are at first covered with a 

 white crust, which soon falls away, exposing the soot-like 

 mass of spores, which are globose, minutely warted, dusky 

 purple or brownish, 10-13 //, diameter. 



When produced in considerable quantity, the dense masses 

 of spores are said to injure vegetation by a process of suffoca- 

 tion. It is not a parasite. 



Instances are also on record where horses and other 



