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Bulletin American Museum of Natural History. [Vol. XXIII, 



Fig. 4. Silhouette of a queen Atta 

 scvdens in the act of manuring her fun- 

 gus garden. (From an instantaneous 

 pliotograph after J. Huber.) 



Often several of these drops may be clearly seen scattered over the young 

 fungus garden [Fig. 6]. According to my observations this performance 

 is repeated usually once or twice an hour, and sometimes, indeed, even 

 more frequently. It can almost ahvays be observed a number of times in 

 succession when a mother ant that has no fungus, as sometimes happens 



in the cultures, is given a piece of fun- 

 gus belonging to another Atta female or 

 from an older colony. The mother ant is 

 visibly excited while she explores the gift 

 with her antennse, and usually in a few 

 minutes begins to divide it up and re- 

 build it. At such times she first applies 

 each piece to her vent in the manner 

 above described and drenches it with a 

 fecal droplet." From these observations 

 Huber concludes that the droplet must 

 be liquid excrement and that the fungus 

 owes its growth to this method of manuring. A direct use of malaxated 

 eggs for this purpose was never observed and could not be detected by mi- 

 croscopical examination, although a number of observations show that the 

 same result may be accomplished indirectly, namely by the female eating her 

 own eggs. This habit is so common and apparently so normal that Huber 

 estimates that 9 out of every 10 eggs are 

 devoured by the mother, often as soon 

 as they are laid. The life of the Atta 

 female in her little cell during all this 

 time is very rh}i:hmical. At regular in- 

 tervals she conscientiously examines the 

 walls of the cavity, flattens out the earth, 

 etc. She devotes more time to licking 

 and manuring the fungus garden and, of 

 course, lavishes most care on the brood. 

 As soon as the larvpe appear they are 

 fed directly with eggs thrust into their 

 mouths by their mother. Huber con- 

 cludes that this is their normal diet till the first workers hatch. He never 

 saw the female either eating the fungus mycelium herself or feeding it to 

 the young. As proof of his contention he cites the case of one of his Atta 

 queens who brought up a brood without a fungus garden. With the 

 appearance of the firstling workers, which are minims, that is members of 

 the smallest worker caste, a change comes over the colonv. They begin to 



Fig. 5. Silhouette of a queen Atta 

 scrdens replacing in the fungus garden 

 tuft of mycelium saturated with fecal 

 liquid. (From an instantaneous pho- 

 tograph after J. Huber.) 



