ANIMALS AND PLANTS 243 
mals which devour them, but a certain number of the 
seeds carried away are not eaten, and these are thus 
distributed more widely than would be the case were 
they to fall to the ground directly. Where the seed 
itself is not the edible part of the fruit, but is enclosed 
in an edible pulp, there is no question that we have 
to do with a case of special 
adaptation. In such cases, e.g. 
most of the ordinary cultivated 
fruits, the fleshy edible portion 
is eaten and the seeds rejected. 
Or, if the fruits are small, the 
whole fruit is eaten and the 
seeds pass uninjured through 
the body of the animal. Birds 
are especially important agents 
in the distribution of seeds, on 
account of the long distances 
over which they travel. Fia. 54, — A, spikelet of a grass 
tatmihy. (Hordeum murinum), the 
Another method of distribu: Honig: agar farnlahed. oth wes 
tion of seeds and fruits through curved barbs; B, part of the 
, awn enlarged to show the 
the agency of animals is seen in _ barbs; C, fruit of bur-clover 
the development of organs of Notiae any aero 
attachment, such as the awns of ag (Cynogios- 
grasses, the hooks and barbs de- 
veloped by the fruits of many Composite, Borragina- 
cee, etc. (Fig.54). The pedestrian who returns from a 
ramble through the fields, covered with'a varied assort- 
ment of “burs,” is but acting as Nature’s unwilling 
agent in the distribution of her plant children. Those 
plants which we call weeds — burdocks, beggar’s-ticks, 
hound’s-tongue, bur-clover—owe their success in the 
