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among these perhaps is the destruction of the fruit bodies. Many 

 animals feed upon mushrooms. Sheep, for instance, are very fond 

 of certain kinds, especially the larger puffballs. Rabbits, also, make 

 use of these delicacies whenever they get a chance, and it is said that 

 turtles are quite fond of varying their diet by eating mushrooms. 

 Slugs habitually feed upon various kinds of mushrooms, as likewise 

 do crickets. 



But the greatest amount of destruction is brought about by still 

 smaller animals. Maggots, which are the young of small flies or gnats, 

 are sometimes very destructive in beds of cultivated mushrooms. The 

 eggs of these insects are usually laid just at the top of the stem where 

 it is attached to the cap. They hatch in about three days, and at once 

 bore into the mushroom and riddle it in a short time. Seven to ten 

 days later they burrow into the ground, and after spending from four 

 to seven days there they emerge as adult gnats, and each one lays 

 about one thousand eggs for the next generation. So abundant are 

 these gnats that in hot weather there are certain kinds of wild mush- 

 rooms that become infested so quicklv that it is almost impossible to 

 collect any that are fit to eat. 



Mushroom mites are sometimes troublesome. These little insects 

 are closely related to the cheese mites and they multiply even more 

 rapidly. It is very difficult for mushroom-growers to get rid of them 

 because they cling to the bodies of flying insects and are thus carried 

 from place to place. 



A very interesting interrelation of mushrooms and animals is 

 found in certain tropical countries. Occasionally while one is walking 

 through a tropical forest he sees in front of him a distinct green line 

 which seems to be in motion. Closer examination shows this to be 

 composed of a large number of ants marching single file and each one 

 carrying over his back a piece of green leaf. These are leaf-cutting 

 ants, or "umbrella ants" as thev are sometimes called because of their 

 habit of carrying pieces of leaves over their backs. They have made 

 a visit to some tree and are now returning to their nest for the pur- 

 pose of making a garden. The pieces of leaves will be chewed to a 

 pulp and then spread out over a place that has been thoroughly cleaned 

 off. On this they will plant the mycelium of a mushroom and in a 

 few days they will have an excellent mushroom garden. These ants 

 take good care of their garden, weeding out undesirable fungi, and 

 in return they obtain an ainmdant supply of food. The mushroom 

 which they cultivate is called Rocifcs gongylopJiora and is one of the 

 umbrella type of gill fungi. Usually, however, the ants do not allow 

 it to produce fruit bodies. Years of cultivation has caused the fungus 

 to produce abnormal outgrowths — little, upright, club-shaped bodies — 



