. The Canadian entomologist. Entomology. 142 'rHE CANADIAN ENTOMOLOCIST The observations by wliich these data were obtained were made in the following manner: Card-board discs one foot in chameter were placed in an infested held and equal amounts of similarly mixed bran mash put in the center of each. By the use of a pair of field glasses counts were made of all grass- hoppers either feeding or within the six inch radius of the baits (Fig. i) at 15 minute intervals from daylight until dark. Fresh mash was supplied when needed to avoid possible error due to drying. Experiments were run on Aug.
. The Canadian entomologist. Entomology. 142 'rHE CANADIAN ENTOMOLOCIST The observations by wliich these data were obtained were made in the following manner: Card-board discs one foot in chameter were placed in an infested held and equal amounts of similarly mixed bran mash put in the center of each. By the use of a pair of field glasses counts were made of all grass- hoppers either feeding or within the six inch radius of the baits (Fig. i) at 15 minute intervals from daylight until dark. Fresh mash was supplied when needed to avoid possible error due to drying. Experiments were run on Aug. 8, 1919, with six cards and again on Sept. 25 with 12 cards. The accompanying curve shows the number of hoppers feeding at each 15 minute interval during these two days. (The time used in these curves is that prescribed by the Daylight Saving Law of 1918 and 1919.). Fig. 1.âCanlboanl tlLsk in i>o^'ition in tli.' field .showing bran Ixiit and gra^^shoiyix^rs at tract tMl to it. Although the grasshoppers were much more abundant on Aug. 8 than on Sept. 24. there was but little difference in their maximum feeding periods. The curve for Aug. 8 shows a marked fall at -'^- ^^- "i"*^ again at ^â M., undoubtedly due to the changing of l)aits at A. M. and P. M. On Aug.,8 the greater part of the feeding occurred between A. M. and ]'. while on Sej)!. 24, 9 A. ^I. and I'- ^'- niarked the limits of this period. ()n Aug. 8 there was considerable feeding activity in the afternoon until when it dropped suddenly until at which time the last hopper was observed to have fed. C)n Sept. 24 feeding activities gradually decreased after P. the iast being recorded at P. M. observations indicate that the maximum feeding period for grasshoppers under these conditions occurs between .\. M. and P. M. (new time). Therefore, to obtain the best results from the use of poison bran mash it should be applied in
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