REPORT OF THE STATE ENTOMOLOGIST I906 61 



numbers even as late as the latter part of October. A number of 

 infested leaves, portions of plants, were received October lo, through 

 Mr Haines, from Rhinebeck. They were placed on soil the 12th 

 and at that time no pupae were manifest. The first adults appeared 

 on the 22d, others emerged subsequently to the 26th, when about 

 four were bred out. Another individual was obtained November 3 

 and lived to the 5th at least. Owing to the fact that the plants 

 could not be well cared for, it is probable that the period of the 

 appearance of the flies was somewhat abridged by the unnatural 

 conditions. The data above shows that not over 10 days are 

 necessary from the time the larvae forsakes the plant till the appear- 

 ance of the perfect fly and it may possibly be a little less. No pupae 

 were observed on the leaves and there is no doubt but that the insect 

 normally undergoes its final transformations in the soil. 



Remedies. The parent fly appears to be closely limited to the 

 plants about which it breeds and apparently very local in habit. 

 This leads us to suggest that it would be advisable to take every 

 precaution to avoid the introduction of thfe pest with newly set 

 plants, since a little effort along this line would result in com- 

 parative immunity during most of the season. 



Another important factor in checking this insect appears to be 

 keeping the temperature as low as possible in the early fall. The 

 injuries were much more marked, for example, in certain houses 

 where there was an attempt made to hasten the growth of the 

 plants by- keeping them warmer than usual, than in other houses 

 where there was no effort made to force the plants. 



The experience of violet growers apparently indicates that fumi- 

 gation with hydrocyanic acid gas is of comparatively little service 

 m checking this pest. This is probably to be explained by the fact 

 that they have been unable to give this treatment at a time when a 

 majority of the flies were abroad and before a considerable pro- 

 portion of the eggs had been deposited. It is presumably true that 

 this powerful insecticide is of comparatively little value in killing the 

 larvae, though it should be most effective in destroying the flies. 

 Evidence at hand indicates a marked periodicity in the appearance 

 of this insect and it is probable that a little observation would result 

 in securing data which would enable a grower to fumigate at a 

 period when most beneficial results could be obtained. 



Periodical cicada (T i b i c e n s e p t e n d e c i m Linn.) . This 

 insect, on account of its large size and its appearance in hosts 

 at long intervals in different localities, is of great popular interest. 



