272 - THE VEGETABLE WORLD. 
the pollen-grains of the flowering plants, but considerable obscu- 
rity still surrounds the question. Mr. Valentine traced an evident 
analogy to ovules in cells closely resembling the parent cells of 
pollen and spores. While Schleiden thought he observed fertilisa- 
tion of the supposed ovules by the smaller spores. The view 20W 
entertained by the best authorities as to the reproduction of the 
mosses is that the Antheridia are male organs which by means of 
the spiral filaments exert a fertilising influence upon the Pistil- 
idia. But no such fertilising process has actually been observed 
in the mosses, the evidence being only circumstantial. 
THE Mosszs. 
The Mosses, which now number not less than ten thousand 
species, are humble plants, but they have no insignificant part t0 
play either in the economy of Nature or in the physiognomy of the 
landscape. ‘Trees, walls, rocks, and ruins assume a smiling 
picturesque aspect under their mossy covering in its varied colours. 
The Phascum, growing in the gravelled alleys of woods and 
gardens, are so very minute that in some cases they scarcely 
attain the height of the hundredth part of an inch. The Hypn™ 
which often clothe the banks of brooks in shady places, oF sare 
small islets at the foot of willows and poplars, or attached ae ey 
trunks of these trees, are vigorous vegetable organisms which do 
not readily perish. The Fontinalis are small grass-like mosses 
which float in the middle of running brooks. The Sphagnums grow 
in marshy places, where they perform an important part in ge” 
tion of bog turf. These aquatic mosses grow very rapidly, exten to 
ing their roots in such a manner as to occupy by degrees the ide 
interior of the pool which they occupy. Their thin and delica 
tissues absorb more than sixteen times their weight in water; ®” 
when they die they accumulate in the bottom of the water, me 
form with mud and the detritus of other plants a mixture fo ; 
when consolidated by time, is cut out in oblong squares, ee 
the name of peat-turf forms an important article of domesti¢ si 
im some countries. : of 
The Polytrichum, commonly called the golden moss, 18 0R° 
the most elegant of its kind ; it is larger than the common 
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