LARVICIDES 293 



theatre. Many materials were tried, including fly sprays, and only a 

 mediocre success obtained. During the later stages of the development 

 of the New Jersey larvicide it was given a trial and the results were at 

 once attractive. 



The tests began in 1930 and continued with increasing numbers 

 through the years to 1935. At that time since it was desirable to obtain 

 correlated figures, cooperating agencies, principally mosquito commis- 

 sions, were requested to file reports covering the following points : de- 

 scription of location, size of area sprayed, type of sprayer used, dilu- 

 tion of larvicide, date and time of day applied, amount of diluted larvi- 

 cide applied, species of mosquitoes present before spraying, frequency 

 of biting before spraying, protection from biting after spraying, length 

 of time protection lasted, number of people conducting the test, injury 

 to vegetation, discomfort encountered by men, and discomfort encoun- 

 tered by women. 



Some of the most significant results are shown on Table XI. 



A detailed description (8) of an operation at the Newark Schools 

 Stadium will be of interest in this connection : 



"It may be of interest to describe here the following incident observed 

 while applying the larvicide in the Newark Schools Stadium, the largest 

 area ever treated (approximately sixteen acres), where four open air 

 concerts were held. It occurred during the third concert, on the evening 

 of July 2. Due to heavy rains during the previous week the Passaic 

 Valley became flooded and was breeding heavily. We were warned by the 

 Essex County Mosquito Commission to expect a heavy brood in the sta- 

 dium. This prediction was substantiated by three mechanical traps 

 stationed in nearby untreated localities. Some 200 female mosquitoes, 

 mainly A. vexans, were caught in the traps during the evening. Observa- 

 tions on previous evenings disclosed that the mosquitoes were starting 

 their flight from the marshes into the stadium grounds about 8:15 p.m. 

 (daylight saving time), becoming very numerous at 8:50 p.m., and di- 

 minishing at 9 :30 p.m. On the afternoon of July 2, many mosquitoes 

 were found within the stadium in the grass, especially near the fences 

 and under the bleachers. These became active when disturbed. At about 



6 P.M. the entire area was thoroughly sprayed and the atmosphere 

 fogged with larvicide diluted 1—10. A survey of the area was made at 



7 :30 P.M. by four inspectors, and not a single active mosquito could be 

 detected. Since the mosquito flight was expected to take place with the 

 wind, which was at that time blowing from the south, several inspectors 

 were stationed on that side of the stadium in order to detect the begin- 

 ning of the flight. Also, a 400 gallon 'Bean' sprayer (supplied by the 



