16 



BULLETIN 377, U. S. DEPARTMENT OF AGRICULTURE. 



Audubon Park, New Orleans, with the Nickels sirup in the strength 

 as recommended originally, and also double, half, and quarter 

 strengths. One gill of sirup was used to a jar, each jar being 

 placed on its side to give free access to the ants, to prevent the 

 entrance of water, and to prevent mold. The " Hall " furnished 

 ideal conditions for the experiment, the temperature throughout the 

 year being kept high and uniform. The abundance of various 

 species of scale insects and aphids attracted the ants in great num- 

 bers at all seasons, but especially in cold and wet weather. Three 

 jars of each strength were used and observations were made fre- 

 quently for a period of 32 days. At the time of this experiment 

 the ants were very numerous, due to the extremely wet summer of 

 1912. The rate of attendance and relative repellent value of the 

 four strengths of the poison are shown graphically in the first part of 

 Table I. 



TABLE!. Experiments u~it ft sodium arsenite (NaAs0 ) added (in Jour strengths*) 

 to sugar sirup solution, 1912. 



[Symbols: A= Heavily visited by ants. B=Only attended by a few ants. C=Not attended by ants ] 

 FIRST TEST, IN HORTICULTURAL HALL. 



DUPLICATE EXPERIMENT, USING PAPER-BAG SIRUP CONTAINERS TACKED ON FIG 

 TREES (OUTDOORS). 



Double strength 



Nickels solution-- 

 Half strength 



Quarter strength. 



.10 pounds granulated sugar + T> pounds II_>O + 1 ounce NaAsO 2 . 

 .10 pounds granulated sugar + 5 pounds H 2 O + J ounce NaAsO 2 . 

 -10 pounds granulated sugar + 5 pounds II 2 O + ', ounce NaAsO 2 . 

 _10 pounds granulated sugar + 5 pounds H 2 O + i ounce NaAsOg. 



