:33 



buildint: at. ("aiiit'ruii wlirn Ww scfci'iis wci-f h'l't Dprn at tin' 

 time of day when tlii'v wen' ll\iii^-. and .Mr. .M. \V. McCall 

 s'atcd lie had noticed tlie s;iiiie Ihiiiii' in previous years. The 

 tl ree sp(':iies comnion at Canin-on are T<ib<ii\u^ llneola (lined 

 horsefly), T. '^-macula I us. and 7'. coshilis ( ureeii-head horsefly), 

 and ai'e Ihe oni^s upon which my ol)servations were made. 

 The Station l)uildinu- is much Ihe hiruest buihlinij in the 

 locality, is constructed in the form of a cross and is painted 

 a clear wliite. I have never fully satisfied myself as to thi^ 

 n ason foi- tliis sti-anji'e l)ehavior of the flies, for there may be 

 two 01- three reasons for it. They may l)e attracted by the white 

 color of the building', or by the shade which it atfords, or they 

 may possibly enter it through a desire to secure protection from 

 their enemies. The flies that entered a doorway, about 5x7 feet,, 

 i.i Ave houi-s' time, on Auiiust 28. whcMi killed nearly fllled a 

 (juart measure, and almost all of them were females. This 

 observation su^jg-ested that a trap might be constructe<l that 

 v.^ould accomplish similar i-esults, and accordingly, in 1905, the 

 tiap was built, but by the time it was ready the horseflies were 

 almost gone and did not appear in sufficient mnnbers again 

 while 1 was in that locality to give me an opjiortunity to observe 

 its workings. 



While preparing a paper on the Tabanidu' of Ohio, 

 it was suggested that, since nuiny horseflies lay their eggs over 

 water, and also since the larva^ fT-om these eggs nmst drop into 

 the water when they hatch, kerosene on the surface of the water 

 iidght be usetl to kill these imnuiture forms, and a measure 

 of success was obtained when the oil was used on stagnant ponds. 



Since, as shown above, varit)us species are ver,v uniform 

 in placing their eggs, theiv may be times when a .s\'stenuitie 

 gi;thei-ing of these will give [)i-actical results. It is often possi- 

 ble to And places whei- ■ as -many as 60.000 may be gathered in 

 a single hour. This would be practical, if at all. in a country 

 whei-e tlu're i.s <;n]y once in a great while a place for these flies 

 t 1 oviposit. 



