PLANTS THAT KEEP AN ARMY 53 
The vetches are of the class of plants which make 
a practice of bribing creeping and crawling insects 
to leave their honey untouched because they know 
that they must be fertilised by flying insects. In 
addition to the sweets stored in their blossoms, the 
plants have tiny glands, filled with sugar, located 
below the flower; and this is offered as a bribe to 
the unwelcome, crawling guest. But this is not all 
the protection the plant has: there are numerous 
sharp-pointed hairs protecting the passage-way to 
the flowers. As a result of these precautions, the 
ant usually eats the proffered sweets and leaves the 
nectar in the blossoms for more favoured winged 
insects, who pay for their honey by distributing the 
pollen of the plant. 
Many plants make servants, or allies, of the ants; 
and others keep such a vast number of protectors 
that they may be termed their “standing armies.” 
A good example of plants that keep servants and 
live stock is one of the ferns, Polypodiwm nec- 
tariferum. This fern receives ants as most wel- 
come guests and allies; it furnishes them with a 
good home and food in the form of honey; in re- 
turn they protect the fern from various forms of 
insects and leaf-cutting ants, thus maintaining mu- 
tually satisfactory arrangements. 
Not the least singular instance of intelligence dis- 
