February, '10] ENTOMOLOGISTS' DISCUSSION 43 



pine. By following up this method, it will be possible to control to 

 some extent the damage caused by this insect. 



Mr. Headlee .- Do I understand that a new coupling has been de- 

 vised for use on the gypsy moth work? We have had considerable 

 trouble with the couplings which we have used on hose in our spray- 

 ing work, and I would be glad to hear more about this plan. 



Mr. Eane : ]\Ir. Worthley and Mr. Guptill have devised a new style 

 of coupling which has proven of great value in the gypsy moth work. 

 I hope Mr. Worthley will explain the coupling fully. 



Mr. Worthley : One of the troubles which we have always had in 

 our spraying work has been that the diameter of the hose at the coup- 

 ling was considerably reduced, when we used those now on the mar- 

 ket. This being the case, it has been necessary to use li/o-inch hose 

 in order to carry a sufficient amount of liquid. 



The new coupling which has just been devised is of the same size 

 as the inside of the hose, so that the stream is not choked when pass- 

 ing through the coupling. 



This will enable us to use 1-inch hose, and will reduce the expense 

 of equipment and the labor involved in laying lines of hose for spray- 

 ing operations. 



Mr. Sherman : The last few papers on the program have detailed 

 two radically different methods of spraying, and the remarks made 

 by Doctor Headden seem to indicate that we should depend on some 

 other method than heavy arsenical treatment in order to control leaf- 

 eating insects. These matters are of great interest to the entomologist 

 and should be more thoroughly investigated. 



Mr. Frost : I w^ould like to make some remarks in regard to the 

 injury to trees as a result of spraying with arsenical poisons. 



Since 1896 we have repeatedly treated many trees, of all kinds, 

 with arsenate of lead, and in this work have used about one pound to 

 ten gallons of water. In spite of this fact, I have failed to see any 

 trees which showed signs of injury from the poison. 



Many people are prejudiced against spraying if they are led to 

 believe that the trees will be injured, and this has caused considerable 

 trouble and annoyance in the past. 



It seems as though, if the trees were going to be injured by arsenical 

 spraying, many of them would have died from this cause in eastern 

 Massachusetts, but I have been unable to find any indications of this 

 trouble. 



Mr. Worthley : I would like to ask Doctor Headden if forest and 

 shade trees are injured by arsenical poisons in the same way as orchard 

 trees. 



