147 DISPERSAL OF SEEDS. 
any stalk. This plant gives usa good example of one of Nature’s 
means of taking care of the seed until it is ripe and able to fly away 
to reproduce its species. When the Coltsfoot is in flower the 
flowering stalk is erect, with the flower exposed to the full force of 
the sun. As soon as the flower fades, the top of the flowering 
stalk bends over in such a manner that the disc of the flower is 
looking to the ground, and the close strong bracts of involucre 
protect the unripe seeds against the weather. As soon as the seeds 
are ripe the head is once more erect, and the seeds fly off in the 
breeze. 
The various species of Thistle also have a sessile pappus, and in 
some cases it isa very beautiful structure; it is easily transported 
long distances through the air, We have about a dozen species of 
Thistles, and a number of varieties and hybrids in this county. A 
great many other composite plants possess a pappus. Among them, 
the Groundsil, which spreads with great rapidity on waste land, the 
Sow-thistle, the Hawk-weeds, and many others. The Thistle down 
has a certain commercial value, it is used to stuff cheap quilts in 
place of Eider down. 
Many other orders of plants have species with a pappus of some 
description, and it is not always the same part of the flower which 
develops into the crown of hairs. In the case of those just mentioned 
it is the calyx; in the Bullrush it is the perianth; this plant 
produces a great quantity of seed in the large “candles” as the 
flowering heads are often called. It is capable of being carried long 
distances, so that its abundance in ballast pits and other ponds is 
easily accounted for. 
The Willow-herb (Epitonium) has a large number of seeds in long 
pods, each of which has a crown of long hairs. Clematis seed has a 
long bearded awn, which helps it to fly through the air. The Cotton 
grass, (ERtopHorum), that adorns our boggy places, with its pure white 
heads swaying in the breeze, is another instance of the perianth 
