OBSERVATIONS ON ANTS IN THEIR RELATION 

 TO TEMPERATURE AND TO SUBMERGENCE. 



ADELE M. FIELDE. 



Although this paper finally treats of measures for the extermi- 

 nation of ants, the experiments 1 herein recorded were begun with 

 a view to ascertaining the temperature preferred by ants and con- 

 ducing to their rapid development in artificial nests. 



The ants employed were Lasius latipcs, yellow, translucent ants, 

 from four to five millimeters long ; Stcnanuna fulvnin, brown 

 ants, from six to seven millimeters long ; Camponotus pennsyl- 

 I'aniciis, black ants with dense integument, from eight to eigh- 

 teen millimeters long. The ants were chosen with reference to 

 color and size, a colony of Camponotus whose members varied 

 exceedingly in stature having been previously captured. 



A special nest was made, affording opportunity for the ants to 

 choose temperature agreeable to them. It consisted of a copper 2 

 half-cylinder, three centimeters in diameter, in which the central 

 portion of the interior, one meter or forty inches in length, was 

 partitioned from the further extending ends, lined with white 

 blotting paper apart from the copper, and imbedded, concave 

 side upward, in cotton wadding which extended slightly over the 

 edges of the half-cylinder at its sides. The half-cylinder was 

 made level, so that gravity should not influence the behavior of 

 the ants. The central portion was kept dry throughout, that the 

 influence of humidity might be eliminated. It was covered with 

 glass microscope-slides laid transversely, and topped with blotting 

 paper so as to secure uniform darkness within. The layer of 

 wadding between the edge of the copper and the glass roofing 

 admitted sufficient air for the ants to breathe, and left no interstice 

 for their exit. 



At the right-hand end the bare copper extended beyond the 

 supporting table and was heated by an alcohol flame. At the 



1 These experiments were made at the Marine Biological Laboratory, Woods 

 Roll, Mass., in June, 1904. 



2 Material suggested to me by Dr. G. H. Parker. 



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