3O2 A. M. FIELDE. 



The ants recovering after submergence were those of large 

 stature among their kind. 



DWARF ANTS. 



The ability of the larva to successfully enter the pupal -stage 

 of development at any time after about half its normal size has 

 been attained, helps to assure the persistence of a harried com- 

 munity. Under propitious conditions the larva grows to the size 

 of an adult ant, expels the contents of the alimentary canal, and 

 eats nothing during the five or ten days preceding pupation. 

 But if suddenly deprived of food it may enter the resting stage 

 when half-grown and may ultimately become a perfectly formed 

 dwarf. I sequestered many fat, healthy, half-grown larvae of 

 Stenamma fnhntvi, put them in the care of fewer nurses than 

 could regurgitate food to all of them, and supplied but little 

 nutriment to the segregated group. Many of the larvae soon 

 entered the resting stage and later on became dwarf workers, 

 only three or four millimeters in length, while the length of 

 workers of their species is usually from five or seven millimeters. 

 A corresponding diminution in the stature of a man would take 

 from one to two feet from his height. The dwarf workers were 

 wholly normal in their faculties and activities, and were markedly 

 assiduous in their care of the young. On the other hand, larvae 

 poorly fed may miserably linger, as if waiting for better times. 

 In one case under my observation, an ill fed larva remained such 

 for one hundred and forty days, although constantly in summer 

 temperature, and it then died without pupating. 



DEPRIVATION OF FOOD. 



Although ants manifestly suffer and soon die if deprived of 

 water, they can exist for many days without food. In the fol- 

 lowing tests the ants were kept in Petri cells, ten centimeters in 

 diameter, and not more than five ants were enclosed in any one 

 cell. All the cells were kept in darkness or very dim light. At 

 intervals, never exceeding four days, the cells and the enclosed 

 sponges were cleansed with 80 per cent, alcohol, to prevent micro- 

 scopic growths which might furnish nourishment to the ants. 

 The cells contained only the ants used in the experiment, and a 



