76 



MASS. EXPERIMENT STATION liULLETIN 2.3i 



rood 

 1. Water 



2. Water, 1 part 

 Honey, 1 part 



3. Lead arsenate l'/2-50, 1 part 

 Honey, 1 part 



Lead arsenate l'/4-50( ^ 

 Lime-.sulfur 1 -40] 

 Honey, 1 



5. Lead arsenate 

 Black-leaf "40" 

 Honey, 



6. Lead arsenate 

 Lime-sulfur 

 Black-leaf "40" 

 Honey, 



7. Limp-sulfur 

 Black-leaf "40" 

 Honey, 



8. Lime-sulfur 1-40, 

 Honey, 



9. Black-leaf "40" 

 Honey, 



I'/o-SO) 

 1-lOOOj 



1 V- -50] 



1-40 [ 



• 1-lOOOJ 



1-40) 

 ' 1-lOOOj 



1 part 

 1 part 



1-1000, 



part 

 part 



1 part 

 1 part 



1 part 

 1 part 



1 part 

 1 part 



1 part 

 1 part 



All Bees Dead Reaction of Bees 



94 hours Quiet; peak of mortality in 30 

 hours. 



517 hours Fed in normal manner. 



70 hours Peak of mortality in 1.5 hours. 

 Bees fed readily and showed 

 typical symptoms of arsenical 

 poisoning. 



73 hours Peak of mortality in 20 hours. 

 Bees fed freely. 



24 hours Bees repelled at first, but soon 

 fed. 



27 hours Bees fed after 2 hours. 



nor. i,„„,.e Bees fed after 2 hours, but fed 

 "•■^ hot! IS sparingly. 



271 ho\ir.s Bees fed very soon. 



Peak of mortality in 24 hours. 



370 hours Bees distinctly repelled. 



Fed barely enough to maintain 

 life. 



The toxicity of tlie different materials varied greath'. Lead arsenate 

 alone and in all its combinations was very toxic. Lime-sulfur alone or 

 combined with nicotine sulfate was far less toxic. Nicotine sulfate alone 

 was the slowest of all the materials to kill. This was due to the fact that 

 it was so repellent to the bees that they fed but slightly upon it, and that 

 the nicotine probably volatilized so tliat much of the toxic principle was 

 dissipated. 



It is significant that lead arsenate in certain combinations was much fast- 

 er in its killing action that when used alone. The mixture of all three 

 materials, which is the regular combination recommended for spraying, 

 proved to be one of the most toxic of all. 



Symptoms of poisoning. 



Bees poisoned by the combined spray soon became sluggish and, although 

 able to vibrate their wings slightly, appeared soon to have lost the power 

 of flight. They began to stagger about, twisting and tossing their abdomen. 

 Attempts to crawl soon became more and more feeble, the legs appearing 

 to be paralyzed and unable to support tiie body. There were occasional 

 periods of violent tossing and spinning about, becoming gradually shorter 

 and more infrequent. In the last stages, the bees became practically motion- 

 less except for occasional feeble and spasmodic vibration of legs and an- 

 tennae. They usually died with abdomen much distended and tongue pro- 

 truded. 



When the bees were poisoned by lead arsenate alone, the symptoms were 

 practically the same as above except the twisting and tossing about were 

 more violent. 



