648 The Outline of Science 



bird gets its feet washed clean at some other place the seeds are 

 liberated from the clodlets, and thus there is scattering of seeds. 



Many facts [Darwin writes] could be given showing how 

 generally soil is charged with seeds. For instance, Prof. 

 Newton sent me the leg of a red-legged partridge (Caccabis 

 rufa) which had been wounded and could not fly, with a ball 

 of hard earth adhering to it, and weighing six and a half 

 ounces. The earth had been kept for three years, but when 

 broken, watered, and placed under a bell glass, no less than 

 82 plants sprung from it: these consisted of 12 monocotyle- 

 dons, including the common oat, and at least one kind of 

 grass, and of 70 dicotyledons, which consisted, judging from 

 the young leaves, of at least three distinct species. 1 



When a bird is killed and rots away on the earth, or is buried by 

 sexton-beetles, the undigested seeds in its crop may, similarly, be 

 sown far from where they were gathered. 



Ants and Seeds 



Ants are particularly fond of seeds which have "oil-bodies" or 

 "food-bodies" on their coats, e.g. violet, bluebell, mignonette, and 

 fumitory. In some cases they eat only the external "food-body," 

 so that the seeds thrown out from the ants' nest may still germi- 

 nate. Moveover, in many cases the seeds are lost by the ants as 

 they are carrying them home. Professor F. E. Weiss placed the 

 seeds of gorse and broom, which have very distinct food-bodies, 

 on the ants' tracks, and found that they were soon picked up, while 

 the seeds of various other plants were left alone. It is reasonable, 

 therefore, to conclude that ants assist in the distribution of gorse 

 and broom. 



1 



Freshwater Mussels and Minnows 



Another example of the way in which one creature depends 

 on another for the continuance of its kind may be found in the 



1 Origin of Species, p. 328. 



