THE MYCETOZOA 



element in this result is the absence of further nourishment. In a 

 cultivation of Badhamiu utricularis, after the plasmodium has been 

 supplied with abundant food, arid has increased largely in bulk, the 

 formation of sporangia may generally be induced by withholding 

 the supply of fungus, which is the food material of this species. 

 If while food is withheld a suitable substratum, such as clean 

 sticks, is supplied, the plasmodium will generally creep on the 

 sticks and there form into sporangia. 



The mode of formation of the sporangia in this species may 

 be described as characteristic of the majority of Mycetozoa, the 

 principal departures from the type being subsequently noticed. 



As seen by the naked eye, the plasmodium previously extended 

 in a diffused network over the substratum is seen to become 

 aggregated in lobed masses 0*5 to 1 mm. in diameter, which in this 

 species are grouped closely together, and vary in number from a 

 few to many thousands, in proportion to the size of the plasmodium. 

 These are at first connected by the veins of the plasmodium, and 

 may be seen to expand and contract in accordance with the 

 direction of the streaming movement, which is still maintained. 

 Gradually, however, the veins connecting them diminish, and soon 

 the whole protoplasm is completely segregated into distinct lobes, 

 or young sporangia. 



While the formation of the sporangia is in progress, all re- 

 maining foreign bodies which have been 

 ingested with food in the plasmodial 

 stage are expelled, and a secretion takes 

 place of a structureless, transparent sub- 

 stance which serves for the support 

 and enclosure of the spores. At the 

 surface of each of the lobed masses, 

 constituting the young sporangia, is 

 thus formed a sporangium wall, which 

 in the mature state is a thin wrinkled 

 membrane, completely investing it. At 

 the constricted base of the sporangium 

 this is continued to the substratum as a 

 slender stalk of varying length (Fig. 9). 



While the sporangium wall is 

 secreted on the surface of the spor- 

 angium, a similar process occurs along 



certain tracts throughout the interior, a , a group of sporangia of Badhamia 



aivino- risp /in tnia cnpr>if>cA fn an -mocrn utricularis. X 12. b, a cluster of 

 giving rise (in tniS Species; to an anaSCO- spore s ; c> a single spore ;d, part of the 



mosing network of flat bands with capillitium containing lime granules. 

 , . . b and d x 170. (After A. Lister, 18.) 



broad, thin expansions at the points ot 



junction (d). From a superficial resemblance to a structure in 



Gasteromycetous Fungi, this network traversing the interior of 



