April, '10] WASHBURN: EMPOASCA AND PAPAIPEMA 163 



As proof that no winter eggs are laid on herbaceous plants we cite 

 the results of experiments in which such plants badly infested during 

 the summer and fall of 1908, and still plainly showing the effects of 

 attack, were brought into the insectarj' and kept in the cold room 

 through the winter. Upon some of these plants living specimens were 

 found as late as October 8th. No individuals, however, survived the 

 winter, nor did nymphs emerge from the tissues in the spring of 1909. 



June 4th. No adults on apple trees, but nymphs in all stages. 

 Adults found on alfalfa adjoining apple orchard, but no nymphs, 

 this being a further proof that this insect does not pass the winter in 

 the egg stage on alfalfa. Sweeping this field from time to time resulted 

 in securing the following collections of adults on the dates named: 

 June 4th, 46 ; June 9th, 91 ; June 11th, 192 ; June 14th, 177. On the 

 12th and 13th there were heavy rains, which may account for the 

 falling off from June 11th. June 21st, 268, one nymph first stage. 

 This is the first appearance of summer broods on herbaceous plants 

 according to our observations. The field which we had been using 

 was then cut, and the following observ^ations were made on a smaller 

 field: June 25th, 275 adults and a few nymphs of the first stage. 



July 9th. Nymphs on clover in large numbers, no nymphs on 

 alfalfa. 



August 24th. Raspberry leaves badly infested. 



August 26th. No egg blisters on apple branches. 



September 13th. Egg blisters present on apple trees near clDver 

 field in considerable numbers, so numerous that probably egg laying- 

 had begun several days previously, yet it would seem that ovipositing 

 was still going on at that date, since these blisters were not so numer- 

 ous as they were late in the previous fall when egg-laying was over 

 with. 



September 17th. Very few nymphs found on alfalfa and clover. 



Number of Broods : May 21st eggs hatched in insectary from 

 apple twigs collected by Franklin in the fall of 1908. Since the 

 emergence of these nymphs from the egg blisters may have a possible 

 bearing upon remedial measures, I may be pardoned for taking the 

 time to describe the process. The nymphs emerge from the blisters 

 through the opening made by oviposition, making this opening some- 

 what larger during the process. We found that if the weather was 

 warm emergence was complete in a few minutes. In one case it took 

 five minutes from the time the vertex of the head appeared until it 

 got completely out of the blister. In another case it took over thir- 

 teen minutes. Young hoppers were observed still emerging from egg 

 blisters in large numbers as late as May 26th, at which time the 



