DISPERSAL BY ANIMALS 71 
except in wet weather. The seeds of both these 
plants emit a mucilage when wetted, and they are 
small enough to be washed away easily by rain 
runnels, which play a very considerable part in 
short-distance dispersal: they begin their career 
with a good bath, and end it, perhaps, after a long 
journey through the air, adhering firmly to a flying 
leaf. 
(d) Dispersal by Animals 
Of all the agents for dispersal, animals, no doubt, 
offer the most extensive field for observation: many 
different kinds carry about seeds in incredible quanti- 
ties, and it is not at all difficult to make observations 
of the greatest interest. 
If we live in the country and have in our home a 
cat that is given to hunting at night, we shall be 
surprised, on applying a comb to his coat, to find how 
many seeds it contains. In my own small garden there 
are three weeds which I root up whenever I see them. 
I could not understand how they got there until I 
combed the cat, but then the puzzle was a puzzle 
no longer. They are the Enchanter’s-nightshade, the 
Cleavers and the Yellow Avens, and a glance at the 
illustration will help us to understand the matter. 
I get them regularly every year, simply because the 
cat goes hunting in the places where they grow and 
brings them home in his coat, from which they drop 
or get rubbed off here and there, as he enjoys a roll in 
the sun, on one or another of the flower borders. It 
is, of course, the hairs and hooks which cause them to 
stick in his fur. 
Again, if we have a dog of healthy instincts that 
comes home sometimes covered with mud, and if we 
pick the pellets off his coat and keep them moist 
