It is one of the hardest things in all the world to understand how balanced is this scale of foe and friend. One year there is a wiping out of our insect friends through frost or floods or microscopic disease, and, freed thus from the check which kept their numbers down, the foes to our plants can multiply to such an extent that nothing we can do will save our crops from total failure. Next year, perhaps, the parasitic beetle, finding such a wealth of food to live upon, increases and holds well in check the pest which last year ate up all our plants. Each wave of insect pests could be explained, no doubt, if all the facts were known, and nowadays no one who knows what modern agriculture means will fail to reckon on the risks from losses caused by these pests. [Illustration] THE CLOVER LEAF WEEVIL (_Phytonomus punctatus_, Fab.) Could anyone suspect this modest antediluvian creature coming toward you out of the gloom, hanging his head, as it were, of any designs against anyone? He has them, however, and if you will examine your clover leaves in June you will find them scalloped with irregular patches eaten out of them. It would be easy for him to prove an alibi, since it is his other self, his larval existence, which does it and does it at night, too, coming up out of the base of the clover plant where it hides during the daytime. Occasionally in August he can himself be seen feeding on the clover leaves. In his two existences he manages to do a good deal of damage to the clover fields of the farmer, necessitating the plowing up of old fields when he becomes too numerous. But let us look at the company he keeps. He is in the same class with the alfalfa weevil which came over from central Asia recently and spread through the alfalfa fields of Utah, threatened the alfalfa growers with ruin and set the Entomological Bureau of the Government out on the trail of some parasite, some enemy of his which they were sure must have held him in check in his native land. If you could have heard the conferences which were held and the drastic measures relating to traffic which were proposed you would realize that it is no child's play to fight the Asiatic relative of this modest-looking creature. But it has in this country worse relatives even than the alfalfa weevil. It is related to the cotton boll weevil, which has brought thousands of families in the South to the point of starvation and drawn millions of dollars from the federal treasury of the country in an effort to fight it and lessen its ravages throughout the cotton belt of the Southern states. Thousands of lectures are being given to tell the farmers what its habits are and how it can be prevented.