274 THE MONTHLY BULLETIN. 



THE NEED OF CHEMICAL ASSISTANCE IN THE STUDY OF INSECTI- 

 CIDES AND FUNGICIDES. 



During the past two years an effort has been made to arrange a card 

 index of the references in agricultural and chemical literature to insecti- 

 cides and fungicides and allied topics. As a result, many thousands 

 of cards have been collected. But in this collection suprisingly few 

 cards are found referring to articles which discuss the chemical compo- 

 sition of insecticides or their toxic action upon parasites and the hosts 

 of parasites. 



The number of references to articles on spraying experiments, when, 

 how. and what to spray, etc., is very large. This work has been done 

 mostly by the entomologist, the plant pathologist, and the horticulturist, 

 whose training and viewpoints are not chemical. The effect of remedies 

 upon parasites and hosts has been carefully observed and this or that 

 procedure has been recommended or condemned, as the result of prac- 

 tical experiences. In many cases, the reasons for a decision concerning 

 the suitability of a remedy have been very obscure and the subject of 

 much speculation. Conflicting results have been very often obtained 

 without apparent cause. The weather, the method, the remedy, and the 

 time of application have all been blamed as the cause of failures. These 

 are doubtless all great factors influencing the success of spraying 

 practice. Chemical advice has sometimes been asked and some of the 

 points elucidated. This advice is frequently given after making some 

 simple laboratory tests without any very extended investigation. The 

 chemist's time and attention is usually well occupied in the investigation 

 of other problems, and his assistance is given by way of making a few 

 determinations to confirm theories, and work of this character is gotten 

 out of the way as soon as possible in order to go on with the regular 



work. 



Of recent years the need of chemical aid has become more and more 

 apparent to assist in the solution of some of the vexing problems that 

 confront the worker in this line of activity. JMuch of the work incident 

 to the administration of the Federal Insecticide Law, and the insecticide 

 and fungicide laws in operation in a dozen or more states, is of a chem- 

 ical nature and has created an absolute necessity for a more compre- 

 hensive knowledge of the materials which these laws seek to control. 

 And so there are now a few chemists who are devoting considerable time 

 to the study of insecticides and fungicides, and valuable articles are 

 beginning to appear, written from their standpoint. ]Most of their time 

 must necessarily be devoted to the origination and perfection of methods 

 of analysis, but it is to be anticipated that our knowledge of these 

 important agricultural materials may be greatly amplified and that the 

 valuable work of the entomologist, the plant pathologist, and horticul- 

 turist may be supplemented by the work of the chemist. 



ACKNOWLEDGMENTS. 



No originality is claimed except in the manner of classification and in 

 the arrangement of the table, which is thought to be in the most con- 

 venient form for reference. The talkie is given as being the consensus 

 of opinion found in the published reports of the different experimenters 

 throughout the United States, supplemented by personal consultation 

 with experts in this line of work, and partially verified by investigations 



