LIST OF PLATES 
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Facing page 
Puarte VIII. Prickly pear cactus. A xerophytic plant, practically 
leafless, the work of starch-making performed by the green layer 
of the bark of the flattened stems . : 5 . F 
Pruate IX. Indian pipe, a saprophytic seed-plant, wholly destitute 
of chlorophyll and with scales instead of foliage leaves : 
Priate X. Pollination of thistle flowers by butterflies. The small 
. tubular flowers are arranged in rather showy heads, so as to 
attract the attention of insect visitors 
Pirate XI. The opening pods of the milkweed allow the seeds to 
be gradually and widely dispersed by the wind 
Piate XII. Bur reed fruits. These usually fall into the water, by 
which they may be carried long distances. The plant is an 
aquatic with aérial leaves, like the cat-tail of Plate VII 
Piate XIII A bluejay burying an acorn. Seeds and fruits when 
thus buried are often left in favorable situations for growth 
Puate XIV. A mangrove swamp. The mangrove, as shown in 
this plate, is a sort of pioneer. With its stilt-like, partly aérial 
roots, it grows in the mud beneath salt or brackish water where 
ordinary vegetation cannot flourish 
Piate XV. Oyster fungus on a linden tree and other fungi on a 
decaying stump. ‘The oyster fungus is a saprophyte, living on 
decaying tissue , : . : ? : . ‘ 
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