HORTICULTURI STS 219 



gathered for thatching the entrances to their 

 underground cities. In this surmise, however, he 

 was wrong, as Belt and Fritz Miiller have shown. 

 The leaves are taken down and packed in under- 

 ground chambers, where they ferment and decay, 

 forming a sort of hot-bed of leaf-mould on which 

 the ants grow mushrooms I But why ? 



The Saiiba Ant is a mycophagist ! Well, it 

 might be argued, there are plenty of naturally 

 grown fungi in the forests that the Saiibas could 

 make use of without going to the trouble to grow 

 them for themselves. True, but the naturally 

 grown mushrooms are seasonal, and their appear- 

 ance is modified by fluctuations of temperature 

 and humidity. The human mushroom-cultivator 

 has discovered that by preparing suitable beds in 

 dark places where he can control the warmth and 

 dampness, he can have continuous crops ; but the 

 Saiiba was before him in making this discovery. 



Thomas Belt was not content to observe the 

 leaves piled up on top of the nests. He dug out 

 the underground chambers, and found that some 

 of them were rounded and five inches across, three- 

 fourths of the space being filled with a spongy 

 mass of speckled brown material. There were no 

 green leaves to be seen, but he satisfied himself 

 that the spongy mass was the remains of them, 

 acted upon by damp heat after being finely cut 

 up. Through all the mass ran white threads of 

 fungus mycelium. The ant larvae were brought 

 to these same chambers, and were fed upon bits 



