THE FUNGUS-GROWING ANTS. 



3 3 7 



Moeller undertook to determine the systematic position of the fun- 

 gus. He naturally supposed that the discovery of the fruiting form 

 would show it to he an Asco- or Basidiomycete. Although he failed to 

 raise either of these forms from his mycelial cultures, he succeeded on 

 four occasions in finding an undescribed Agaricine mushroom with 

 wine-red stem and pileus growing in extinct or abandoned Aero uiyrine.r 

 nests. From the basidiospores of this plant, which he called Rhozitcs 

 i/onyylof>lwra, he succeeded in raising a mycelium resembling in all 

 respects that of the ant gardens. Three of the species of Acroin\rinc.r 

 did not hesitate to eat portions of this mycelium and of the pileus and 



FIG. 195. Vestigial nest crater of Trachymyrmex septcntrionalis. (Original.) 

 The nest entrance is at .r, the pile of sand pellets shown in the lower right-hand 

 corner represents the crater of Atta tc.rana and Mccllerius versicolor. 



stem of the Rlwzitcs. He believed, therefore, that he had definitively 

 established the specific identity of the fungus cultivated by the ants. 

 A careful perusal of Moeller's observations shows an important lacuna 

 at this point. That his Attcc ate portions of the pileus and stem of the 

 Rhozites does not prove that it is the fruiting form belonging to the 

 fungus they habitually cultivate and eat. Nor is Moeller on much 

 surer ground when he assumes that the mycelia cultivated by different 



