THE FUNGUS-GROWING ANTS. 



333 



fecal droplets seems now to be abandoned. The mother Atta hence- 

 forth pays no attention to the development of the garden or to the 

 brood, but degenerates into a sluggish egg-laying machine, while the 

 multifarious labors of the colony devolve on the workers. In the mean- 

 time the " kohlrabi " has become so abundant that it can be fed to the 

 larva?. In concluding his paper Huber makes the important observa- 

 tion that fertile females of Atta se.rdcns are readily adopted by strange 

 workers of their own species. Such 

 adoptions may be frequently re- 

 sorted to in a state of nature and 

 would perhaps account for the 

 enormous size and great age of some 

 of the formicaries of the larger spe- 

 cies of Atta, which in this respect 

 resemble the colonies of Formica 

 nifa and F. c.rscctoides in the north 

 temperate zone. 



Only a few of the Attiine ants 

 have spread from their original 

 tropical home into the southern, sub- 

 tropical portions of the United 

 States. These are Cyphomyrmex 

 riniosus var. comalcnsis and subsp. 

 minutus, C. wheeleri, Mvcetosoritis 

 hartmani, Trachyiiiynnc.v sepien- 

 trionalis with the var. obscurior, T. 

 titrrifc.v and arizonensis, Mocllcrins 

 versicolor and its subsp. chisoschsis 

 and Atta tr.rana. I have been able 

 to observe all of these except T. 

 an'zoiiensis in a living condition, and 

 as they exhibit nearly the whole 

 range of Attiine habits they may be 

 very briefly described. For many additional details the reader is re- 

 ferred to my paper mentioned above. 



i. Cyphomyrmex. Our two species of this genus, the most primi- 

 tive in the series, have very different habits. C. ritnosus (Fig. 186, a), 

 which is widely distributed through the tropics, enters the tip of Florida 

 and southwestern Texas. It makes small, concealed nests under stones 

 or logs in rather damp, shady places and collects caterpillar excrement 

 as a substratum on which to grow its fungi (Fig. 187). These are 

 very unlike the fungi raised by any other Attiine ants except Myco- 



FIG. 200. Atta texana. (Orig- 

 inal.) a. Soldier ; b, thorax of same in 

 profile ; c, worker media ; d. worker 

 minima ; all drawn to same scale. 



