June, '22] Strickland: poison molasses for noctuids 219 



In the laboratory, however, and with a few bottle traps, we found 

 that the deterrent effect of quassia is very slight and that it is readily 

 overcome by the addition of a little saccharine to the bait. 



The effect of quassia on moths is very variable and it cannot be 

 predicted for the individual. Moths captured feeding on flowers, 

 were offered a choice of formulae. Those containing quassia and 

 saccharine were preferred to straight molasses. This was also demon- 

 strated in the field. At a strength of two ounces to a quart of solution 

 quassia kills about 65% of all moths that feed on it. In some cases 

 death is rapid, and within ten minutes of feeding either sex of P. ortho- 

 gonia loses all power of locomotion, lies on its back and response to 

 stimulation becomes continually less apparent till it ceases entirely. 

 Death in such cases appears to be gradual and progressive. In other 

 cases moths feed freely on the bait for a few minutes and suddenly flop 

 around the receptacle as though in great pain, till sudden death puts 

 and end to their activity. 



On the other hand some 35% of the moths which have imbibed 

 quassia solution, sometimes more extensively than have those which 

 die, become either very sluggish or quite inactive a few minutes after 

 feeding and they may remain in this condition for two or three days. 

 Sometimes females, which have been quite inactive for over 24 hours, 

 will laboriously struggle to their feet, lay a few eggs, and relapse into 

 inactivity. Recovery in other cases appears to be complete, and since 

 it permits oviposition, we have retained the use of fly pads in addition 

 to quassia. Ovcc experiments indicate that very few moths will recover 

 from the effects of the latter before they succumb to the arsenical poi- 

 son of the former. 



At present our poisoned bait formula, therefore, consists of: — a 10% 

 solution of cane molasses, the diluent being water in which quassia 

 chips have been soaked overnight at the rate of two ounces to the 

 quart. In each bottle of this solution is inserted one fly pad, sufficient 

 saccharine to cover a Canadian 5 cent piece (1 gram), and eight drops of 

 amyl acetate. 



This formula undoubtedly can be improved considerably both as 

 regards its attractiveness and poisoning ability. As it stands, all of 

 the materials, with the exception of amyl acetate which is not essential, 

 can be obtained in any village. 



The present retail cost of materials for a dozen traps, including 

 the bottles, is approximately $2.65. 



We have no definite data as to what distribution of traps will give 

 the greatest returns for money expended, but believe that one to every 



