April, '15] 



ENTOMOLOGISTS' PROCEEDINGS 



179 



In the course of the Texas work the importance of getting rid of the 

 breeding-places in the winter time seems to me to be very great. We 

 have found that by a thorough cleaning-up in the winter we could do 

 very much more than we could by continuing the work during the 

 summer only. 



Mr. E. p. Felt: How about disposal of manure containing over- 

 wintering pupae? 



Mr. E. G. Titus: ^Manure has been carried some distance from the 

 town and we have fairly good assurance that the flies will not come 

 back in the spring. We found some that would go through the winter 

 in the pupal state and these appear to be destroyed when the manure 

 is properly scattered. Where possible the manure is taken out and 

 scattered in fields and we found we could accomplish fairly complete 

 destruction. In other cases, the manure was piled in ricks in the field. 



Mr. E. p. Felt: Does that hold true ia the north where they are 

 frozen up? 



Mr. E. G. Titls: I couldn't say, but I think that hy breaking 

 up the manure and scattering it over the ground you will destroy many 

 of the puparia. We found them hibernating in piles against barns 

 and other protected places, and by cleaning those out you can greatly 

 aid the matter. 



]\Ir. E. N. Cory: I would like to have your opinion of the distance 

 that flies ^^11 travel. 



]Mr. E. G. Titus : We marked somewhere between seven thousand 

 and eight thousand flies the last few years and then hunted for them 

 afterward. We found a few of them but I found no flies at any time 

 a half a mile away from the place where they were liberated. 



In Salt Lake City, Utah, there was complaint that flies were coming 

 from the city dumping-ground. You remember our Salt Lake blocks 

 are large and four of them would make a pretty good-sized distance to 

 walk. In the country we found the same thing, where we took them 

 out into the farm region and liberated them in the pastures, and under 

 those conditions we never found any that would reach beyond half a 

 mile. Now perhaps our conditions are different; the dry air may 

 have something to do vrith it, and I would like to hear if anyone has 

 done anything on that line. It is quite essential on our end of the 

 work on the fly. 



Mr. T. J. Headlee: Mr. C. H. Richardson of our department car- 

 ried on som.e flight experiments during the past season. Flies marked 

 in various waj's were liberated at a distance of 1,715 feet from the pig 

 barn on the college farm at New Brunswick. About three thousand 

 individuals were liberated at a tim.e in one place and in most of the 

 trials from ten to fifteen marked flies were recovered in the traps at 

 the pig barn. 



