1897-] ENTOMOLOGICAL NEWS. 103 



rows and then covered the onions and kainit at one and the same opera- 

 tion and awaited results. The balance of the field was prepared by ap- 

 plying the kainit in the rows before setting the onions. Results: No 

 further trouble or damage was experienced from the maggot on those 

 treated with the top dressing, and none was caused by them where the 

 kainit had been applied in rows before setting. We did find several 

 specimens on onions in this portion of the field, but they had no effect 

 upon the appearance of the onions. The onions set one day were badly 

 infested within three days, and the maggots must have either run their 

 course without doing damage or died from the effects of the kainit. The 

 plot has shown no signs of infestation from that time to this [January 

 5th] and is now apparently healthy and vigorous, promising for an abun- 

 dant seed crop in 1897. 



This experience is interesting in more ways than one. It might have 

 been urged against the first year's work that the benefit was caused as 

 much by taking out the infested onions and destroying them as by the 

 application of the fertilizer, and the criticism would be a just one, but this 

 process was not repeated in other years and the kainit was entirely relied 

 upon. Onions are very largely cultivated in Cumberland County and 

 there are plenty of fields in the immediate vicinity of the one on which 

 the experiments were made where no measures were taken to check the 

 development of the onion maggots. The county grows truck very largely, 

 and radishes and cabbages are also badly infested by root maggots. The 

 Fall experience is an extremely interesting one. It is evident from the 

 history of the case that the eggs were laid upon the onions themselves, 

 while they were in the crates. Evidently there must have been great 

 numbers of the flies about, and the onions piled where they could get at 

 them without any difficulty, attracted them. Just how long the eggs were 

 present it would be hard to say, and so far as I am aware we have no 

 data as to length of time that the eggs of Anthomyiids can remain un- 

 hatched after being laid. It would seem that if any of the maggots had 

 hatched before the onions were set out, it must have been noticed when 

 the tubers were cleaned to examine their color and suitability for the pro- 

 duction of seed. The eggs must have been ready to hatch, however, 

 since three days thereafter onions were taken out in which the maggots 

 were already nearly one-quarter of an inch in length. It seems hard to 

 escape the conclusion that the kainit was effective in this case and the 

 more so, because where the onions were set in the ground to which kainit 

 had been first applied, there was practically no trouble from the maggots. 

 Of course it is impossible to say that in all localities and under all circum- 

 stances the same application would produce the same result, but at all 

 events it would be very well worth the trying. In Cumberland County, 

 where these onions were grown, the soil is very light; mostly sand with 

 an admixture of clay and loam. In times past considerable marl has 

 been used to better the condition of the land, but on the farm in question 

 commercial fertilizers have been chiefly relied upon of late years. The 



