232 ENTOMOLOGICAL NEWS. [September, 



other States. Speaking of London purple, Dr. Lugger says it has the 

 advantage that it can be used witli the Bordeaux mixture, and he says if 

 Paris green is used for a similar purpose, we are very apt to increase its 

 injury upon foliage. This is strictly incorrect: Paris green can be as safely 

 used as London purple with the Bordeaux mixture, but it must not be 

 used with any fungicides containing ammonia, because the ammonia dis- 

 solves the arsenite of copper. London purple, on the other hand, can be 

 used with fungicides of this description, because the arsenite of lime is 

 not attacked by the ammonia. This is a very important point, and one 

 upon which I have always placed great stress. It is the ammonia that 

 renders the use of Paris green inadvisable in any fungicides containing it. 

 Wherever lime is present in the fungicides it will be apt to prevent any 

 trace of injury to the leaves by any of the arsenites. 



The Horn Fly Again. — This insect forms the subject of Bulletin 14 of the 

 Central Experimental Farm, Ottawa, Canada, and in it Mr. Fletcher gives 

 a brief statement of the life-history of the insect, and also a record of its 

 appearance and spread in Canada. Nothing new is added to our know- 

 ledge of the insect, but the Bulletin is mentioned here principally to record 

 the fact that in New Jersey the fly is becoming less and less abundant. In 

 several localities in the southern part of the State, where, a few years ago, 

 the fly was in the greatest abundance, they are now very much less in 

 number than the common stable fly, Stonioxys calcitrans. Exactly what 

 has led to this reduction in numbers I have no means of knowing, but 

 the fact is undoubted. 



The Boll Worm.— This insect forms the subject of Bulletin 29 of Division 



of Entomology United States Department of Agriculture, and it is written 

 by Mr. F. W. Mally. The Bulletin is an excellent one. It is too long to 

 abstract with any degree of justice, and only its scope can be mentioned 

 here. The method and extent of injury on various plants are recorded, 

 the life-history of the species is given, the parasites are mentioned and 

 briefly described; the insects preying upon it are referred to, and finally 

 the injuries to the plants caused by other insects and charged to the Boll 

 worm are detailed. The subject of remedies forms the most important 

 part of the Bulletin, and is, of course, the most interesting. Attacking 

 the insects by light proved distinctly unfavorable, or, as Mr. Mally says, 

 " that the use of lights for attracting and trapping the Boll worm moth is 

 entirely useless." The use of poisoned sweets seems to have been more 

 successful. Applied to pea vines, which had been planted as a trap crop^ 

 a great many moths were poisoned, and probably a considerable benefit 

 was derived by this method. Mr. Mally, however, does not seem to think 

 very highly of this method either, and does not speak very enthusiastically 

 of it. Quite a number of experiments were made with pyrethrum, either 

 dried, a watery extract, or an emulsified oil extract. All of these were 

 more or less successful on the young larvae and all were practically un- 

 successful on the old or more matured larvae. The final conclusion is 

 that, trapping the larvae upon corn planted for that special purpose, would 



