INSECTS AND FUNGI 233 



to occur ; indeed, though combs without larvae may be found, 

 there are none without fungi in the nests of the species named. 

 Without such segregation it is difficult to see how blind larvae 

 could be prevented by blind workers and soldiers from eating 

 what was nearest to them, especially if this had hitherto been 

 their only food. And if the differentiation were due to this 

 cause, we should still have to account for its occurrence in 

 species which do not cultivate fungi. 



The Agaric 



There is yet a further point of agreement with Moller's 

 discoveries. As soon as conditions are at all favourable — often 

 before any other species appears — an agaric grows from the 

 termite combs and pushes through to the surface, sometimes 

 from a depth of three feet. On digging down to the comb, 

 one finds that it is covered with mycelium (very fragile, owing 

 to partial decay), and that it does not contain any larvae. The 

 fungus has got the upper hand, and the cultivation has " run 

 to seed." Apparently this occurs whenever the comb reaches 

 a certain stage of decay, and other observations seem to indicate 

 that when this happens the whole comb is re-eaten by the 

 termites. Sometimes more than fifty of these agarics begin 

 to develop from a single comb ; but, as a rule, only one succeeds 

 in reaching the surface — the others remain aborted in the 

 chamber, and are subsequently eaten. The agaric is fairly 

 common — indeed, in some districts it is the chief edible species ; 

 but it is never found except growing from termite nests. 

 Unfortunately it is a pink-spored species {Volvaria eurhiza), and 

 (as is usual in this group) it has not been possible to obtain 

 the germination of the spores. The connection between the 

 spheres and the agaric is therefore only a matter of probability. 



The "Weeds" 



Is the fungus garden of the termites a " pure culture " of the 

 fungus, or may there be other species in it ? From the behaviour 

 of fungus spores which the insects eat with dead leaves and 

 wood, it may be assumed that the comb material is sterilised 

 by its passage through the alimentary canal. How the spores 

 of the agaric are introduced is not yet known. It does not 

 seem probable that they are conveyed from an old to a new 

 nest by the insects, and yet none of the termite fungi have 



