ENTOMOLOGICAL SOCIETY. 



already imported from foreign countries, and which will be discussed later on in my 

 paper. While it has not been deemed best to discuss, in detail, legislative control of such 

 destructive species as have already been colonized here in this country, and many of them 

 widely diffused, yet their possible control in many cases at least, by the application of 

 nature's own forces seems to me to constitute a very important feature of International 

 Entomology. 



Forms of both plants and animals, unaided by the influences of man, make their 

 way over the face of the earth but slowly if at all, and it is probable that a species often 

 becomes so influenced by the change that it loses its specific identity and takes on new 

 characters, so that the specialist rechristens it and gives it another name. The result of 

 all of this is that wherever a species makes its way, naturally, its enemies usually follow, 

 or else while undergoing the process of adaptation, new enemies come to exert their 

 influence. In other words, the difference between an artificial and a natural introduction 

 is much the same as suddenly dumping an iceberg into a pond, as against allowing the 

 same amount of water to make its way into the pond, from the same source, but through 

 a small spring or brook. In the former case both equilibrium and temperature are dis- 

 arranged, while in the latter the effect is too gradual to cause any radical changes. 



The legitimate introduction of plant life from one country into another has come to 

 be a matter of vast commercial importance, and, adding as it does to our health, comfort 

 and pleasure, such introductions are in every way commendable. Accidental introduc- 

 tions may, however, not always prove so satisfactory. Now, all of this brings me to the 

 second phase of the subject of International Eatomoloey, viz., the intentional, if not 

 indeed necessary, introduction of exotic insects in order to re-establish the equilibrium 

 that has been upset by the importation of plant life, or, as is sometimes the case, to 

 enable the plant introduced to become permanently established. 



Of species of insects purposely introduced from one country into another, there are 

 those whose products constitute articles of commerce, of which the honey bee and silk 

 worm are well known illustrations. The importation of large quantities of the ova and 

 imagines of two species of American aquatic hemiptera, Corixa mercenaria, Say, and 

 Notonecta americana, Fabr., from Mexico, where they are used for human food, into 

 England, where they are to be used as food for birds, game, fish, etc., is another illustra- 

 tion of a different feature of this commerce in insect life. 



The relations of insect to plant life are, however, so various and intimate ; and, 

 because of their reaching out over the face of the globe for the fruits, grains and orna- 

 mental vegetation of other climes, men are finding themselves more and more driven to 

 import insects foreign to their respective countries. In some instances it has been found 

 impossible to permanently establish an exotic plant without insect assistance. We all 

 remember how impossible it was to get the red clover plant established in New Zealand 

 until humble bees were also imported to fertilize the bloom, as the plant is not one that 

 will perpetuate itself indefinitely from the roots ; and at present we in the United States 

 are unable to grow the perfect Smyrna fig owing to a lack of the good offices of a little 

 foreign insect, Blastophaga pensens, which actually represents the male element in its 

 fertilization. 



Lastly, we come to what appears to be the most important of all insect importations, 

 viz , the introduction of foreign, carnivorous insects, whose office in their native country is 

 to prey upon and destroy those that are destructive, which last we have unintentionally 

 imported into this country on trees, plants and shrubs, or in the fruits and grains coming 

 to us from these same countries. That is to say, when we find that we have introduced a 

 destructive species of insect, we are to go to the native habitat of this and there secure its 

 native insect enemies, and introduce these to hold the former in check, as they do at 

 home. 



Parasitism is nature's insecticide — one of the forces that is employed by nature to 

 restore equilibrium, so to speak, among natural organisms in point of numerical strength. 

 The observing entomologist may every year witness proof of this, for he will observe some 

 species to increase very rapidly during a short time, and, knowing of their fecundity, will 



