HORTICULTURISTS 223 



A clear space is left all around this spongy mass 

 which at no point is allowed to come in contact 

 with the walls or roof. The mass is held together 

 by threads of mycelium, and upon its surface are 

 innumerable minute round bodies of a white colour 

 which Moller termed " Kohl-rabi clumps." These 

 are the " mushrooms " which form the principal 

 food of these ants, and for whose successful cultiva- 

 tion they cut and manipulate the leaves used in 

 preparation of the spongy mushroom-bed. The 

 fungus was found to be Rozites gongylo-phora. If 

 the nest is broken open and the spongy mass scat- 

 tered, the ants show as much solicitude in gathering 

 up the fragments — especially the newer portions — 

 as in saving their grubs. 



In observation nests where these ants were 

 supplied with Cuphea-leaves they were seen to 

 divide the latter into minute fragments, which 

 were crushed in their jaws until not a cell of the 

 leaf structure remained uninjured. It was then 

 rolled into a ball of pulp, and added to the fungus- 

 bed. Cyfhomyrmex, an allied genus of ant, is also 

 to be included among the fungus growers : likewise 

 A-pterostigma. The latter lives in decaying wood, 

 and the triturated wood-fibres mixed with the 

 excrement of wood-boring beetles are used for the 

 composition of the mushroom-bed. 



An ant of Trinidad {Sericomyrmex ofacus) has been 

 described by Mr. F. W. Urich as making its nests 

 in clayey soil, with a cylindrical shaft to the outer 

 world standing about an inch above the soil. About 



