154 THE ORIGIN OF SPECIES 



may safely assume that under such circumstances their 

 rate of flight would often be 35 miles an hour; and 

 some authors have given a far higher estimate. I have 

 never seen an instance of nutritious seeds passing 

 through the intestines of a bird.; but hard seeds of 

 fruit pass uninjured through even the digestive organs 

 of a turkey. In the course of two months, I picked up 

 in my garden 12 kinds of seeds, out of the excrement 

 of small birds, and these seemed perfect, and some of 

 them, which were tried, germinated. But the following 

 fact is more important: the crops of birds do not secrete 

 gastric juice, and do not, as I know by trial, injure in 

 the least the germination of seeds; now, after a bird has 

 found and devoured a large supply of food, it is posi- 

 tively asserted that all the grains do not pass into the 

 gizzard for twelve or even eighteen hours. A bird in 

 this interval might easily be blown to the distance of 

 500 miles, and hawks are known to look out for tired 

 birds, and the contents of their torn crops might thus 

 readily get scattered. Some hawks and owls bolt their 

 prey whole, and, after an interval of from twelve to 

 twenty hours, disgorge pellets, which, as I know from 

 experiments made in the Zoological Gardens, include 

 seeds capable of germination. Some seeds of the oat, 

 wheat, millet, canary, hemp, clover, and beet germinated 

 after having been from twelve to twenty-one hours in the 

 stomachs of different birds of prey; and two seeds of 

 beet grew after having been thus retained for two days 

 and fourteen hours. Fresh-water fish, I find, eat seeds 

 of many land and water plants; fish are frequently de- 

 voured by birds, and thus the seeds might be transported 

 from place to place. I forced many kinds of seeds into 



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