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THE STUDY OF A LICHEN FROM OBAN. 
As a sample we may take the Lichen which forms the 
subject of this paper, as it is one of a family of plants 
often overlooked, sometimes even despised; yet how amply 
will these plants repay a little careful study— 
* “ That not alone in trees and flowers 
The spirit bright of beauty dwells ; 
That not alone in lofty bowers 
The mighty hand of God is seen ; 
But more triumphant still in things men count as mean.” 
Nor do the poets alone value the lowly lichen, but the 
artist, too, has learned to value those humble plants, which 
impart their rich velvety tints and give such soft beauty to 
the rocks and trees in his landscapes. But to the scientific 
botanist the Lichens form a link without which the chain of 
Nature would not be complete. Their constitution still forms 
a battle-ground for our most advanced cryptogamists, while 
much interest is aroused by the age to which the Lichens are 
supposed to attain, and their capabilities of enduring great ex¬ 
tremes of climate, some species flourishing in the tropics and 
others in the temperate zone, while some attain their utmost 
luxuriance even amidst the snows of the frigid zone itself. 
It is certain that provision is made in some kinds of 
Lichens to endure great changes of the surrounding elements, 
to resist alike the withering effect of continued drought and 
the more fatal influence of excessive moisture—qualities 
which must tend to a long continuance of existence. 
Certainly more information could be collected on these 
points, and a more careful study of the Lichens in these 
different conditions would soon shed a clearer light upon 
their life history. 
The particular species of Lichen to which we wish now 
to confine our attention is called liicasolia amplissima, and is 
usually found growing upon trees in shady situations, and 
from one of the charming woods near Oban our specimen 
was gathered (Fig. 1). 
The tliallus, or leaf-like expansion, consists of several 
very distinct parts, as you will see by reference to the 
drawing (Fig. 9) ; c represents the cortical layer, which is 
composed of layers of dense cells somewhat flattened by 
pressure, and although so much thickened in their cell Avails 
still retaining sufficient transparency (especially when moist) 
to a.lloAV the bright green hue of the gonidia to be seen 
through them. 
We next come to the gonidia! stratum marked g in the 
drawing, which consists of a vast number of spherical cells, 
each containing green granular matter. These cells seem to 
