ALLIES OF THE PLANT WORLD 
Primrose, Cowslip and Polyanthus, often car- 
ried by insects, is deeply furrowed, covered 
with spines and knobs, strung together by sticky 
threads and, in other ways, provided with ap- 
paratus which enables it to adhere to any ob- 
ject which it touches. 
The pollen of the Hollyhock and the Dande- 
lion consists of large, beautiful, spherical grains 
covered with spikes. The Rhododendrons, 
Azalias, and Fuchias produce great masses of 
grains bound together by viscid threads. Many 
of these bits of life-principle are geometric mas- 
terpieces. A pollen grain of the Cobaea Scan- 
dens is one of the most fascinating objects of 
the microscopic world. It is perfectly spheri- 
cal and cut into small hexagonal facets like the 
eyes of a fly. Grains of pollen of all kinds vary 
between one two-thousandth and one two-hun- 
dredth of an inch in diameter. 
Alliances between plants and birds are more 
important than we imagine. ‘The tropical 
Humming-birds and the eastern Sun-birds are 
in habits exactly like the pollen-carrying in- 
sects. ‘To watch one of these brilliantly col- 
oured creatures hovering over a flower or flying 
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