AN INTRODUCTION TO THE STUDY OF LICHENS. 85 
The muscles of the diaphragm, the laryngeal muscles, the muscles 
of the fore-arm and leg, the intercostal muscles, and the massateric 
muscle, from all of which by the aid of the dissecting (curved) 
scissors or knife thin slices must be cut in the direction of the 
fibrils. The slices must then be put in the centre of a drop of 
water upon the glass plate of a strong compressorium teased out 
with needles moistened with acetic acid and glycerine, covered 
with the top glass of the compressorium, and placed upon the stage 
of the microscope. If trichinze are present they will be recognised 
as pale ovoid swellings situated between the muscular fibres; these 
are the cysts in the interior of which the worms are coiled up. 
M. Tikhomiroff, a Russian savanf, has described a method for 
the disintegration of muscular fibre for facilitating searches for 
trichine. The suspected meat is cut into small pieces and digested 
for half an hour in a mixture of one part of nitric acid and one 
part of chlorate of potash ; upon transferring to distilled water and 
agitating with force the muscle splits up into very fine fibres, on 
some of which the fusiform swellings of the encysted trichinze are 
easily perceptible if present. The last method is not recommended, 
although in good hands it might yield excellent results, still the 
mixture of nitric acid with chlorate of potash is an exceedingly 
corrosive fluid, and even explosive under certain conditions, and 
consequently should be used with great caution. 
AN INTRODUCTION TO THE STUDY, OF 
LICHENS: 
By THE Rev. W. JOHNSON. 
HE group of Plants, which is to occupy our consideration in 
this paper, has until recently, been regarded as the “approbria” 
of our Cryptogamic Flora; and these humble members of the 
vegetable kingdom may still be soregarded by many people. But, 
when we become acquainted with the Lichens, when we take time 
to behold their hidden beauty, to understand their structure, their 
habits, uses, and modes of growth; when we feel the thrill of 
enthusiasm which they can impart, and when the frail things, dried 
in the herbarium, gather around themselves some of the sweetest 
associations of our life—associations redolent of the woods, the 
heaths, the mountains, and the shore; then, disregard of them, 
much more despising them, becomes a matter of surprise. Disre- 
gard, or despicable feelings in relation to Lichens, may arise from 
ignorance ; but they cannot arise from any lack in the plants them- 
selves of those qualities which create and sustain interest ; nor, 
