OBSERVATIONS ON ANTS. 1/3 



died within a day. Another Stcnaunna revived forty-three 

 hours after the same exposure and lived at least seven days. 

 One Cainponotus gave the first sign of returning life fifty-seven 

 hours after its exposure of one minute to the heat and was more 

 than a week in convalescence. 



Lasius latipcs. - - When exposed ten seconds to heat at 50 C. 

 twenty-three per cent, revived. When exposed for fifteen sec- 

 onds none revived. 



Stenamma fulvum. When exposed to a temperature of 50 C. 

 for ten seconds, forty per cent, revived ; when exposed for fifteen 

 seconds, fourteen per cent, revived ; when exposed for thirty 

 seconds none revived. 



Camponotus pcnnsylvanicus. When exposed to temperature 

 of 50 C. for thirty seconds, all revived ; when exposed for one 

 minute, fifty per cent, of those of the largest stature revived ; 

 when exposed for two minutes, none revived. 



Throughout the experiments, the smaller ants succumbed 

 under the shorter exposures, while the larger ants were those 

 that survived the longer exposures ; but a temperature of 50 C. 

 sooner or later proved fatal to all. 



SUBMERGENCE IN COOL OR COLD WATER. 



That the ants were killed by the heat and not by asphyxiation, 

 when the medium was water, was shown by the fact that the ants 

 succumbed during a like period of exposure whether in water or 

 in air equally heated. But I tested the effect of submergence in 

 cool or cold water and found that the ants survived such sub- 

 mergence for comparatively immense periods. 



When ants are submerged they struggle or crawl about for a 

 few minutes only, after which they sink and appear to have died. 

 Many groups of ants were submerged with the following results : 



Lasius latipcs : Group a. Fifty per cent, revived after twenty- 

 seven hours' submergence and were alive and well six days later. 

 The revivals all occurred within two hours after the ants were 

 removed from the water to a moist sponge. 



Stenamma fulvum : Group b. All revived after eighteen 

 hours' submergence. 



Group c. Seventy-five per cent, revived after fifty-two hours' 

 submergence, and were alive and alert two days later. 



