76 MISCELLANEOUS EESULTS OF WORK OF BUREAU IX. 



28 gallons of the solution at the rate of one-half ounce of 98 per cent 

 cyanid to each gallon of water. At the time of this treatment there 

 were thousands of ants either actually in attendance on the "lice" 

 or running about between the nests and the infested cantaloupe vines. 



At 6 p. m. on September 2 the treated strip was examined. Dea 1 

 ants by thousands, at some places in heaps, were lying on or about 

 the nests. Many dead specimens were also found out in the field 

 from 6 to 10 feet from the nests. However, at every nest there were 

 still a few live ants. Practically all of these survivors had gathered 

 about the nests and it was difficult to find a live ant out in the field, 

 where at the time of the treatment they occurred in surprisingly large 

 numbers. 



In order to test the effect of a second treatment applied soon after 

 the first, two nests near the center of the strip were given a second 

 application at 5.30 p. m. September 3. This was considered as 

 Experiment No. 4. In this experiment 2 gallons of solution at the 

 rate of one-half ounce cyanid to each gallon of water were applied 

 to each nest as before. 



An examination made of these nests on the following afternoon 

 (September 4) showed that although a few additional ants had been 

 killed no practical advantage had been gained by this treatment, 

 and this conclusion was not altered by frequent later examinations. 



Along the entire treated strip the ants which remained alive seemed 

 demoralized for about a week, but by September 1 1 several small col- 

 onies had again started. The cyanid solution does not penetrate very 

 deeply into the nests and it is evident that the pupse escape destruc- 

 tion unless they are very close to the surface, and on reaching ma- 

 turity they are able, with the remaining live ants, to reestablish the 

 colonies. 



By September 16 one or two of these colonies (nests) had reached 

 fairly good size and although the ants were moderately common 

 they occurred in very much smaller numbers than they did at the 

 time of the first general treatment (September 2). This first treat- 

 ment left the nests with a "crust" of compact soil over the surface. 

 At two or three nests, just under the crust, the ants had large numbers 

 of pupae and at a few other nests a considerable number of winged 

 adults had crawled out and was clustered about the openings. 



At this date (September 16) all the nests in the entire strip were 

 again treated with 25 gallons of the solution at the rate of one-half 

 ounce of 98 per cent cyanid to each gallon of water. A particular 

 eff"ort was made to soak the winged specimens and the pupae. All the 

 adults touched were readily killed, but the pupae showed no immediate 

 effect from the treatment. 



An examination made on the following afternoon showed that 

 although the number of ants had been very considerably reduced 



