THE OUTLOOK FOR E 



business man and a market gardener — all three 

 without the least entomological knowledge. When 

 applied entomology becomes coupled with politics, 

 there is alwaj's danger that it will fall into the hands 

 ot incompetents, or worse — men who owe their in- 

 fluence to politics and political methods. 



In the direction of wise legislation, however, 

 there is much to be done in the immediate future. 

 There is always danger of the importation of for- 

 eign pests, and the different sections of our own 

 country should be on their guard against the intro- 

 duction of injurious insects from other sections. 

 A whole catalogue of pertinent illustrations might 

 be cited. 



(2) The greatest advances of the past few j-ears 

 in the line indicated by the second category, have 

 been in the discovery of the applicability of arsen- 

 ical poisons against biting or masticating insects : 

 in the extension of their use against many species 

 which were not at first thought to be amenable to 

 treatment by them : also in the discovery of simple 

 methods of emulsifying kerosene or other oils so as 

 to permit of their ready dilution and their conse- 

 quent use without danger to foliage. 



The use of Paris green, first successfully tried 

 against the Colorado potato-beetle, and afterwards 

 used extensively against the cotton-worm, the boll- 

 worm, the canker-worm, and more recently against 

 the codlin moth, plum curculio and many other 

 mandibulate species, marks an era in the warfare 

 against insects. Cheaper arsenical preparations, 

 like London purple, have also proved most satisfac- 

 tory. Next, perhaps, in importance, is the discov- 

 ery of the petroleum emulsions, as used against 

 haustellate or sucking insects. Though originally 

 aimed at the cotton-worm and an outgrowth of the 

 cotton-worm investigation under the U. S. Entomo- 

 logical Commission, treatment with these emulsions 

 in their various forms has been extended to all var- 

 eties of bark-lice and plant-lice, as well as to many 

 gnawing insects which chance to feed upon crops 

 which it would be dangerous to spray with arseni- 

 cals. 



Many variations in the preparation of arsenical 

 mixtures and the kerosene emulsions have already 

 been tried, and doubtless many more yet remain to 

 be tried. Necessary variations in special cases 

 often occur. In my search for a proper wash 

 against the fluted-scale, I met with the necessity of 

 finding a mixture which would penetrate the seem- 

 ingly impervious wax covering of the egg-sac, or 

 which would harden it to such a degree that the 

 Jice, on hatching, would be unable to escape. This 



1 NO MIC ENTOMOLOGY. 383 



was finally accomplished by the addition of resin to 

 the washes, and insects of this character, such as 

 the cottony maple-scale {Pulvinaria iuinu/icrabi/is), 

 the Florida wax- scale (Ccroplastes Floridensis), the 

 barnacle scale ( Ceroplastes cij-ropedifonnis) of this 

 country, and the cottony currant-scale of Europe 

 (Pitk'/nan'a n'ljesii), can now be successfully treated 

 at any stage of their existence without the necessity 

 of waiting for the pregnable period of the hatching 

 and migration of the young lice. 



The lessening of the expense of these successful 

 washes is another important point for the future 

 experimenter in this line : and we have before us an 

 immediate need of a careful and exhaustive series 

 of experiments as to the relative effects of the 

 arsenicals and the emulsions upi.m the foliage of 

 different plants. Our knowledge in this direction 

 at present is slight. \ei we should know with cer- 

 tainty not onh- just what effect a certain mixture 

 will have upon the vitality of a given plant, but what 

 effect it will have upon this plant in a particular 

 part of the country, with a particular sun exposure, 

 at a certain time of the da}', with certain conditions 

 of plant-\-igor and precipitation, at a certain season 

 of the year and at a certain period in the life of 

 the plant. We know, from experience, that all of 

 these conditions have strong bearings on the effect 

 of the poisons upon vegetation, yet this line of inves- 

 tigation, first suggested in 1885, has still to be 

 thoroughly followed up. The combination of two 

 classes of insecticides for simultaneous appli- 

 cation to two classes of insects affecting the 

 same crop, as a combination of Paris green and 

 kerosene emulsion for the treatment of apple trees 

 affected with bark-lice and apple-worms, or canker- 

 worms, or the same mixture for young cabbages 

 bearing both lice and caterpillars, will afford oppor- 

 tunity for much useful work in the future. In a 

 like way, the combination of a fungicide and an 

 insecticide for the simultaneous treatment of in- 

 sects and fungous diseases affecting the same crop, 

 is beginning to be practiced and offers a field for 

 future experimentation. 



We look to the immediate future not only for 

 the improvement of substances already in use as 

 insecticides, but in a lesser degree for the dis- 

 covery of new ones. Private individuals, from the 

 commercial standpoint, are continually inventing 

 and placing on the market new insect poisons. In 

 the great majority of cases these remedies are but 

 tributes to the gullibility of the great American 

 public, but we may reasonably expect now and then 

 a disco^•ery of value. It is better to have a dis- 



