101 



pound of Paris green to 215 gallons of water, with a benefit of but 20 

 per cent over untreated trees for the whole season. It is believed 

 that arsenites of lime or soda should be used at the rate of 1 pound or 

 1^ pounds of ASjOj to 160 gallons of water to be effectual, and they 

 are being thoroughly tested at various strengths this year. Paris 

 green, 1 pound to 160 gallons of water, and Disparene, an arsenate of 

 lead, manufactured by Bowker Insecticide Company, 3 pounds to 

 150 gallons, were also tested upon 5 trees each, with 5 check trees, the 

 dropped and picked apples being counted on all. One spraying of 

 Disparene proved as effectual as two of Paris green. It will be 

 noticed that the benefit derived is not so much in the smaller per- 

 centage of wormy picked fruit, though that is marked, as in the 

 very much smaller percentage of wormy fruit dropped, the perfect 

 fruit dropped being approximate!}^ the same for all the sprayed and 

 unsprayed trees. With 60 per cent of the apples wormy upon the 

 check trees, a benefit of 87 per cent for the season was secured by 

 spraying twice with Disparene, of 60 per cent by spraying once, and 

 of 61 per cent by spraying twice with Paris .green. Of the dropped 

 fruit, that sprayed with Disparene twice showed a benefit of 75 per 

 cent, against 52, per cent with that spi'ayed with Disparene once and 

 54 per cent with that sprayed with Paris green twice. Likewise with 

 the picked fruit, Disparene applied twice produced a benefit of 96 per 

 cent, against 66 per cent when applied once and 69 per cent with Paris 

 green applied twice. 



The •periodical cicada has been present the past month in northern 

 Delaware, but so far as ascertained has not occurred in the two lower 

 counties, and I have been unable to secure any records of its occur- 

 rence there in 1885. The pupse first emerged in numbers on May 22, 

 and continued except on a few cold nights until June 2, the most 

 ascending on May 30. Several dogs and cats have been observed to 

 relish the adult cicadas. The turrets or mounds of the pupae were 

 observed under pine and spruce trees on several old lawns and in a 

 piece of pine timber burned over about the middle of May. The 

 largest turrets were found under a small outbuilding, the floor of 

 which was about a foot above the ground. Here the turrets com- 

 pletely covered the surface of the soil, reminding one of a house-top 

 view over city chimneys, and were from 3 to 6 inches long. 



The cicadas have been most abundant upon the lawns of several 

 old estates around Newark, where in some cases they are more numer- 

 ous than in 1885. The woods around Newark are now brown from 

 dying twigs, and one or two young peach orchards have been prac- 

 tically ruined. The injury is only local, however, and not serious 

 generally. It was observed that the pupae upon emerging from the 

 ground were strongly attracted by an acetylene bicycle lamp. On 

 changing its position the pupse would at once turn toward the light. 



