20 



BULLETIN 377, U. S. DEPARTMENT OF AGRICULTURE. 



The jars with the new type of sirup were visited constantly for 

 62 days, or to the conclusion of the experiment. The small amount 

 of sirup left was still clean and as sweet as at first. 



Tests of the poisonous qualities of both liquids were made with 

 colonies in Janet cages, under control as to food. There was prac- 

 tically no difference in toxicity. Workers in 

 both cages began to die in 4 days, the queens 

 stopped ovipositing in 14 days, and winged 

 males died very quickly, the queens in 17 days, 

 and the whole colony in. each case was extermi- 

 nated on the thirtj^-second day. 



PEACTICAL TESTS OF THE IMPEOVED SIEITP. 



The new sirup, made exactly as in the for- 

 mula given above, is A^ery palatable to the ants 

 at any season of the year. It was found that 

 containers charged with it placed at selected 

 points outside a residence would attract the 

 ants and they would cease to invade the house. 

 A private residence in a large plot of ground 

 on a street corner with a row of large oak trees 

 along each street was heavily infested with 

 ants, which were to be found in the sink, the 

 refrigerator, all over the floors, etc. On June 

 18, 6 cans each containing this sirup and a 

 sponge were hung on the brick pillars which 

 supported the house. The following morning 

 there was scarcely an ant to be seen in the 

 house and the ants were attending the sirup 

 in large numbers. The same conditions existed 

 throughout the length of the experiment, which 



was terminated on August 10. Many such small experiments have 



been conducted, the results being equally successful. 



APPLICATION OF THE SIRUP. 



The paraffin-covered paper bag^ shown in figure 4 is undoubtedl}^ the 

 cheapest container. It can be made in large quantities at a cost of about 

 $5 per thousand. Small 1-pound bags used in grocery stores are ob- 

 tained, and two or three holes about one-fourth inch in diameter are cut 

 through each folded bag with a leather-punch or similar instrument. 

 This provides each bag with two holes on each side for the entrance 

 of the ants. Being opened, the bags are dipped in a pan of molten 



Tig. 3. — Comparison of the 

 improved sirup (left) 

 with the Nickels sirup 

 (right) after five months' 

 evaporation. The im- 

 proved sirup is still 

 clear and sweet, while 

 the Nickels sirup is 

 dark and full of crys- 

 tals and decayed mat- 

 ter. (Original.) 



^ The writer is indebted to Mr. R. W. Moreland, Bureau of Entomology, for his sugges- 

 tions in the preparation of this waterproof container. 



