2 HALF HOUKS WITH ESTSECTS. [Packard. 



of many plants, are but examples of the multitudes of ways 

 in Avhicli this dependence of plant and animal exhibits itself. 



The theory of the science of agriculture, now so far per- 

 fected, seems adequate to the end. Every year adds to the 

 perfection of the seed to be sown, as agriculturists are 

 paying more attention than formerly to a careful selection of 

 the best fruits and seed. The chemistry of plants, of nutri- 

 tion and absorption, all the daily routine of plant life, has 

 been mapped out by Liebig and his followers. The care of 

 flocks and herds and their improvement have made our far- 

 mers actually better acquainted with the princiijles of in-and- 

 in breeding, or the secrets of "natural selection" than many 

 naturalists. Indeed, the facts already brought out by prac- 

 tical writers on this subject are important contributions 

 towards a theory of the method and permanent effects of 

 specific variation, a point now so interesting to naturalists. 



Agricultural mechanics, in its constant endeavor to lighten 

 toil and economize time, thus leading to the increased intel- 

 ligence of the laborer, is daily enlarging its borders. New 

 inventions of reaping and ploughing machines and labor 

 saving machinery of every description are constantly devised, 

 so that we may consider the theory of agricultural science 

 far advanced toward perfection. 



Now come in some disturbing agencies, such as tempests, 

 prolonged rains, severe droughts, rust, mildew and injurious 

 insects. Their appearance cannot be prognosticated, their 

 direful effects once experienced cannot be immediately reme- 

 died, nor the remedies Avhen discovered be always seasonably 

 applied. The last mentioned cause of disturbance will now 

 engage our attention. 



Nearly ever}^ one can recall the sudden and simultaneous 

 uprising of the army worm in New England during the 

 summer of 1861. Its ravages have been known and dreaded 

 yearly in the western states, where at intervals it has done 

 wide and extensive damage. Though in a local history a 



2 



