66 



GRASSHOPPERS AND OTHER INJURIOUS INSECTS OF 1911 AND 1912. 



ing a few horses, two days, 8,700 flies ; same place, one day, 12,000 

 (twelve thousand) flies; same place, one and a half days, 18,800 

 (eighteen thousand eight hundred) flies. 



While we wish to emphasize the importance of using bread and 

 milk for bait, it should be noted that if anything more attractive 

 is near by (tainted meat for example) drawing the flies away from 

 the trap, manifestly the thing to do is to place some of the more 

 attractive material in the bait pans, or add it to the bread and milk 

 bait already in the trap. 



Fig. 47. The Minne.sota Fly Trap, showing the three part.s. The 

 uprights at ends are not parts of the trap. 



The recent statement of Prof. M. J. Rosenau and C. T. Brues, of 

 Harvard, based on a series of experiments, that the biting stable 

 fly, Stomoxys calcitrans, is largely responsible for the spread of 



Fig. 48. Outlines of trap, showing structural details. 



