ECOLOGY or ruNGi 71 



underground truffle in the following manner. When the spores germi- 

 nate, they give rise to hyphae which grow over a densely cespitose, com- 

 mon moss, Mnium hornum, which develops a large number of feeding 

 rhizoids, that penetrate the soil to the depth at which Elaphomyces 

 grows. The mycelium of Cordyceps not only covers the aerial portions 

 of the moss, but follows the rhizoids underground until they reach the 

 underground truffle over which the moss may happen to grow. Bot- 

 anists searching for Elaphomyces always know where to look for it by 

 the presence of the Cordyceps hyphae, on the moss Mnium hornum. 

 There is a black beetle, a native of France' with a pale, velvety abdo- 

 men, known as Btdboceras gallicus, about as large as a cherry stone. By 

 rubbing the end of the abdomen against the edge of the wing cases it 

 produces a gentle chirping sound. The male has a horn on his head. 

 This insect burrows in the soil among the trees of the pine forests and is 

 nocturnal in its habits. It descends vertically into the soil in search 

 of the underground truffle-like fungus, Hydnocystis arenaria, upon 

 which the insect rdbassier feeds. The fungous fruit body is about the 

 size of a cherry with a reddish exterior covered with shagreen-Uke warts. 

 The beetle, which feeds upon Hydnocystis arenaria and Tuber Requenii 

 one of the truffles, locates the fungi by a subtle sense of smell. The 

 human truffle hunter finds these underground by the burrows which 

 the beetles make in digging for their chief source of food and he usually 

 finds groups of these fleshy funguses directly beneath the openings of 

 the beetle holes. 



Rozites gongylophora is a gill fungus which is raised as a fodder by 

 leaf-cutting ants in their subterranean passageways in thp tropics of 

 South Brazil. 



On a visit to the Berlin Botanical Garden in 1898, the writer noted 

 the following remarkable examples of sclerotia-bearing fungi: Poly- 

 porus sapurema A. MoUer (Fig. 92, Teil I, Abt. i**. Die naturlichen 

 Pflanzenfamilien, p. 171). The sclerotium is over 30 cm. in diameter 

 and weighs at least 20 kg. It is furrowed and roughened and leather 

 colored. A specimen from Blumenau, Brazil, developed in the Victoria 

 house of the Berhn Garden four large pilei in August and September, 

 1897. Polyporus mylittm found in Australia produces a sclerotium 

 {Mylitta australis Fr.), which as "native bread" is used as food 

 by the natives. Polyporus tuherasler, which grows in the mountains 



' Fabre, F. H.: Social Life in the Insect World, 1912 217-237. 



