April, '16] SANDERS AND FRACKER: LACHNOSTERNA RECORDS 257 



It will be noticed that several species almost disappear at the 

 stations farther northeast, although L. rugosa, duhia, and grandis 

 gain in numbers. An interesting record is the capture of L. duhia 

 at Dodgeville, only previous to May 21, although the traps were run 

 for another month. At Baraboo we took 92 per cent of the catch 

 (377) of this species before the same date, thus indicating unusually 

 earty emergence. 



Large Trap Pans Desirable 



By surrounding the central pan, below the gas lantern, with six 

 similar pans, it was found that 76.4 per cent of the beetles attracted 

 to the light at Ripon, missed the central pan and were caught in the 

 adjacent pans. It was found, also, that a pan placed on the side of 

 the central pan toward the origin of flight caught twice as many beetles 

 as a pan placed behind the light. The desirability of using as large a 

 pan as possible is evident. There appeared to be no relative difference 

 of sexes in the several pans. 



An ordinary barn lantern used for the trap was found to be prac- 

 tically worthless when used less than 100 yards distant from one 

 of the gasoline lights, but when used alone at some considerable 

 distance caught a fair amount of beetles approximating 30 to 35 

 per cent of the efficiency of the gasoline light. 



At the Lancaster station the direction of flight was always from 

 the northwest toward the southeast. This phenomenon can possibly 

 be explained by the fact that the flight seemed to be directed up a 

 valley at the head of which was a fair-sized grove of trees, principally 

 oak, ash and walnut. Another small valley diverging from the 

 first was treeless and there the catch was very light, whereas in the 

 adjoining small valley with trees available the catch was many times 

 larger. Traps near the margin of woods or close to a fringe of trees 

 were in all cases most successful and doubly efficient. 



Economic Results 



Any attempt to draw close conclusions on the beneficial results 

 of the capture of these large numbers of beetles in 1914 would be 

 undesirable and the resulting judgment inaccurate, owing to the nature 

 of the season the following year. The heavy and frequent rains of 

 1915, accompanied by exceptionally low temperatures, resulted in 

 retarded and weak crops. 



Mr. W. A. Johnson, who was in immediate charge of the lanterns 

 at Lancaster, states he feels certain, after constant observation 

 throughout the summer of 1915, that the destruction of more than 

 440,000 beetles on his farm has served as considerable protection for his 



