Man and Nature 409 



By careful quarantine measures and the treatment of tick- 

 infected cattle with an arsenical dip the Department of Ag- 

 riculture has freed some 500,000 square miles of the quaran- 

 tined area in tlie southern states from a pest, which at one 

 time was estimated to cost the nation from $-10,1)00,000 to 

 $100,000,000 annually. For the cattle tick not only does vast 

 damage by transmission of disease, but as a blood-sucker 

 levies a tremendous toll upon the cattleman. It has been es- 

 timated that as much as 200 pounds of blood may be lost by 

 an animal in a single season, while in the case of the horse 

 tick, as much as fourteen pounds of ticks have been dropped 

 from one animal in three days, and probably as much more 

 was still attached. But further, the tick has a companion 

 in villainy, for in the sores which it makes the screw-worm 

 fly deposits its eggs, from which the larvas burrow into the 

 body of the unfortunate victim. 



Our knowledge of the Hy and the mosquito, upon which 

 the campaign against these pests has been based, is largely 

 due to the work of the Bureau of Entomology. 



But space will not permit further discussion of our prog- 

 ress in wealth, health and happiness, due to the work of the 

 economic entomologist. 



The work of ridding the South of the cattle tick is in 

 charge of the Bureau of Animal Industry in the Department 

 of Agriculture, whose duty also it is to wage increasing war- 

 fare upon the animal diseases which are a constant mciuice 

 to the nation's supply of meat, leather and other animal 

 products. Scab mites, which in years past levied a heavy 

 toll upon the cattle grower, have been nearly exterminated ; 

 the foot and mouth disease, which in 1914 was epidemic in 

 twenty-two states, and was seriously threatening the live stock 

 industry of the country, was stamped out after a hard fight ; 

 hog cholera, ever a serious drain upon the hog industry, is 

 gradually being brought under control by the use of a serum 

 and other measures, and an active campaign is now under 

 way for the suppression of tuberculosis in hogs and cattle, 

 a disease serious not alone to the animal industry, but, wiien 

 present in dairy cattle, a very probable nuMuice to human 

 life itself. The work of the Bureau in safeguarding our 

 meat supply is mentioned in another chapter. 



In addition to its campaign against diseases both animal 

 and hunum, the Bureau is also actively engaged in the in- 

 crease and improvement of our supi)lies of meat, milk and 

 other animal products, ])ut details concerning this work would 

 carry us too far afield. 



But the economic biologist is concerned not alone with 

 holding fast that which he hath. 1 1 is duty it is likewise to 



