140 A. M. Botiomle^ and C. Fuller 



In this connection it may be added that whilst the immatures of 

 all fungus growers can be seen browsing upon the spheres, the 

 action is more in the nature of a caress and is not followed by 

 any disturbance of the contour of the spheres. The insects 

 swallow chains of cells. Thus no sphere has the appearance 

 •of being gnawed and none is removed bodily. As Fetch 

 suggests, there are relatively few spheres in comparison with the 

 host of insects; consequently, one cannot avoid the conclusion 

 that every removal is almost at once made good by abnormally 

 rapid growth. There can be no oher explanation and it is 

 quite essential and natural to the economy of the nest that such 

 should be the case. There is not room for many spheres where 

 there are so many insects to be accommodated. 



Sjostedt (1913) described Euiermes agricola as a fungus 

 grower. This termite belongs to Holmgren's genus Trinerviiermes 

 of which there are a number of species scattered over South 

 Africa. The cellular, mound nests of one or another are notice- 

 ably abundant throughout our grassy areas, but no species is a 

 fungus grower in our present acceptance of this term. Although, 

 during the rainy season, either Podaxon pistillaris or P. carcmo" 

 malts — fungi belonging to the Lycoperdaceae or puff-ball family 

 — may be found growing from out of these mounds there is, as yet, 

 no direct evidence of a symbiotic relationship between termite 

 and Podaxon^ Certainly there is a very definite association of 

 nest and fungus and as certainly the latter is tolerated by the 

 insects. It is this toleration which leads one to suspect a more 

 intimate relationship since some mycelial growth, not yet ob- 

 served, may be consumed by the Trinervitermes. The mycelium 

 of the Podaxon is, at times, observable in the intra-cellular 

 matrix of the mound and one is led to suspect that it grows there 

 upon the organic matter of the nest composition or on the matter 

 voided and plastered on to the cell walls by the termites. 

 These Podaxons originate within the cellular spaces of the mound, 

 and here at a depth of one to four inches from the surface, the 

 initial stages of the fruiting bodies develop The Podaxon 

 pushes through the crust of the mound, and after the spores 



