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the more conspicuous foliose and fruticose species first, and will be very 
likely to begin with the lichens of the trees. After finding a few of the most 
conspicuous forms, he will think that he is nearly done, and yet every time 
he goes over the same ground something new will appear. This is the uni- 
form experience, and even the most keen-eyed lichenist finds much of inter- 
est after he has been over a limited area several times. The difference 
between him and the beginner is that he knows from experience that he does 
not detect all the first few times over a spot; while the beginner has to learn 
this, little realizing how few of the many species he sees at first and how 
poorly he distinguishes differences in lichens, at first thinking that three or 
four forms are all one, when perhaps they do not even belong to the same 
genus. But careful study will soon begin to improve the powers of observa- 
tion, and the work will grow and the interest increase day by day. In 
continuing to work on a small area till it has been looked over a dozen times 
or more, one should attempt to find every substratum that might bear lichens 
and take into account all the varied conditions of light, shade, and moisture, 
which cause so much of the variation in species. Look carefully on old 
dying trees, trees in good condition but old with rough bark, and younger 
trees with smooth bark, for rocks in shade and rocks exposed to sunlight, 
the outcrops and the boulders and for shaded and exposed earth. Then 
look for any species of lichens that seem to prefer a particular genus or 
species of tree or a particular kind of rock or earth. And when all this is 
done in an average region, the beginner should be able to find from ioo to 
150 lichen species and varieties within five miles of his home, while in some 
localities such work carried on for two or three years should give the student 
more than 200 lichens. 
Collecting Outfit. 
But before the first trip is made the student will want to know what to 
carry with him on a collecting trip. A good knife is needed to take the lichens 
from the trees with as little of the bark as possible, and a geologist’s ham- 
mer and a good cold chisel, especially tempered for the rocks to be chipped^ 
to get the rock lichens with as little of the rock as possible. Then a hand 
lens is needed to enable one to detect differences in lichens in the field so as 
to know as far as possible whether he is duplicating too much. With the lens 
one soon comes to detect differences in both surfaces of the larger thalli, the 
nature of the exciple and disk, the upper surface of crustose lichens and 
many apparently slight microscopic differences in minute lichens, which 
might otherwise be thought to be the same in the field when they do not 
even belong to the same genus. A bag, basket or vasculum must be carried 
to contain the specimens, and a lot of paper or envelopes so that each kind 
of lichen may be wrapped separately as it is collected. Then there must be 
a pen or pencil so that careful notes may be placed on each envelope 
or in each packet, showing the date of collecting, the name of the substatum 
and the surrounding conditions as to light, moisture and shade, or any other 
data that may be desirable in a particular instance. A sponge is sometimes 
very handy for moistening certain lichens in dry weather so that they may 
be easily separated from the substratum, and a small bottle of water may 
