NEW FORMICID^E FROM BARRO COLORADO ISLAND. 



157 



rootlets left intact by the ants during their excavations. The 

 substratum of the gardens consisted of small, dull-yellow pellets 

 of uniform size, held together and covered by a dense white 

 mycelium, bearing minute clusters (bromatia) of spherical 



FIG. 2. Fungus garden of Sericomyrmex amabilis sp. nov. built in a Petri dish. 

 X i%. Photograph by Dr. David Fairchild. 



swellings ("kohlrabi") like those of Atta, Acromyrmex and 

 Trachymyrmex. Urich's description of the gardens of S. urichi 

 applies accurately to those of amabilis. The pellets of the sub- 

 stratum are undoubtedly particles of soft, chlorophylless vege- 

 table matter collected by the workers in the immediate vicinity of 

 the nest but I was unable to identify them more closely or to 

 observe the ants in the act of gathering them. 



