2 4 o POPULAR SCIENCE MONTHLY 



erations of pure scientists, working for the most part in obscurity, 

 most of the insects in each civilized district have been described and 

 named, and much has been made known concerning their habits. 

 This knowledge is about as important a tool to the husbandman as is 

 his plough. 



In passing it need only be mentioned that the agitation for the pro- 

 tection of native birds, a movement that the farmers are at last begin- 

 ning to support, originated not with agriculturists, but with scientific 

 ornithologists. The farmer, left to his own prejudices, would kill all 

 birds. 



In another way pure science has aided agriculture, in improving 

 varieties. The chief method in use is selection, planting each new gen- 

 eration from the seeds or cuttings of the best plants of the previous one ; 

 the most fit are selected and propagated. This method has been in 

 use for more than a century, but it is only within the past fifty years 

 that it has entered into general systematic employ. The man whose 

 labors brought this method into dominance was Charles Darwin, who 

 proved how important a factor selection is in the perpetuation and 

 guidance of the changes of living beings. Now Darwin was not called 

 a practical man; he was first an insect collector and geologist, then a 

 traveler, lastly a most conscientious experimenter with an eye single 

 to explaining. He discovered a natural factor in evolution, and illus- 

 trated it so fully on both wild and cultivated species that the world 

 has accepted its truth. Before him men had applied selection rather 

 unwittingly, on the general assumption that " blood will tell." After 

 him they saw clearly into the workings of the principle, and now ex- 

 periment with a fixed method. It is Darwin's method that the De- 

 partment of Agriculture is trying to teach the farmers. 



Then much work has been done to secure improvement by the cross- 

 breeding or hybridizing of different varieties. It was Darwin again 

 who was the first broadly scientific investigator of such inheritance. 

 Take two plants or two animals which differ in one or more qualities 

 and cross them, then it is to be expected that the hybrids will differ 

 from the parents, and that a new strain or breed may be obtained that 

 will prove more favorable for our particular purposes. Much of this 

 kind of experimentation, perhaps the greater part, has been done so far 

 by practical animal breeders and gardeners, and it was from such 

 records that Darwin obtained much of his information. No one, for 

 instance, has carried it out more extensively than Burbank, and he 

 has had in mind marketable returns. Yet the theoretical study of 

 hybridizing is coming to aid the other, and in time may come to direct 

 it. Different kinds of inheritance are now distinguished, as blended 

 inheritance, when the hybrid is intermediate between the two parents; 

 mosaic, when it has some of the characters of the one and some of the 



