10 



Many seeds may be dropped by birds in flying away 

 with them, others are distributed in the process of tearing 

 the fruit to pieces, in wiping the beak, in quarrelling over 

 their repast, and other ways. Others are swallowed without 

 injury and are dropped undigested. 



Experiments have been made by Kerner upon a large 

 scale, as to what proportion of seeds eaten by various animals 

 and birds pass through so as to be capable of germination. 

 Generally speaking nearly all the seeds eaten by mammals 

 and by birds were found to be destroyed in the process of 

 digestion. Blackbirds and thrushes being found to allow of 

 a larger proportion passing without injuring them. The 

 visits of other birds are doubtless of advantage to the plants 

 they frequent for food, as, even though they may destroy a 

 large proportion of the fruits they eat, a certain number are 

 distributed, and even the visits of birds which destroy all 

 they eat is an advantage, inasmuch as they scatter numbers 

 of seeds in the act of their depredation. 



It is clear that a hard integument must be of advantage 

 to a seed if it or the fruity pulp in which it is enclosed is 

 used as an article of diet. 



There is yet another way in which fruits intended for 

 food are distributed. Some creatures, such as squirrels, have 

 a knack of keeping hidden stores. Man is not the only 

 forgetful animal, and accordingly it happens that these stores 

 sometimes remain where placed, and there germinate and 

 grow. 



The cases of animal and bird distribution I have been 

 considering are those of mutual accommodation. Another 

 class of cases now presents itself, in which the plant takes 

 advantage of the animal and makes use of him without any 

 quid pro quo. In passing through a wood one has often found 

 oneself covered with clinging seeds, such as those of the 

 common burr or the cleavers. It may not have always 

 occurred to the recipient that these seeds were specially 

 adapted by nature to cling to the clothing of any quadraped 

 or biped who might come in contact with the parent plant, 

 and that when he is spending his time in clearing his cloth- 

 ing of these unwelcome adherents, he is merely performing 

 the office laid upon him by the plant of making the intended 

 and necessary distribution for the next year's growth, in much 



