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spores to fall gently on to paper placed beneath the gills &c., and 
fixing them with collodion; and by means of carefully dried 
sections, and I have seen very satisfactory preparations dried in 
sand and kept in boxes. . 
Nevertheless both in the case of the larger fleshy fungi, and in 
that of the delicate mould fungi—e.g., Mucedines and 
Hyphomycetes—no preparations equal those kept in properly 
stoppered bottles of preservative fluids, and when it comes to 
gelatinous and aquatic fungi I know of no other way of keeping 
them at all, if they are to be examined afterwards. 
At the outset it has to be admitted that no fluid preserves the 
delightful colours in all their beauty, and drawings are absolutely 
necessary as adjuncts to any complete collection. Some success 
is Claimed, however, for recent attempts with various fluids.* 
Of the fluids employed absolute alcohol js no doubt the most 
satisfactory and simplest, and it becomes diluted by the water it 
abstracts from the larger forms sufficiently to counteract the 
disadvantageous brittleness brought about in smaller species. 
But it must be remembered that alcohol in all its forms 
induces changes which render objects preserved in it useless for 
any but comparatively rough and superficial observation later. 
Moreover, absolute alcohol is expensive, and the various cheaper 
forms of alcohol, methylated spirit, &c., cause contractions and 
distortions, and entail other drawbacks in even greater degrees. 
Formalin is excellent for Many purposes of preserving, but its 
keeping powers are limited, and although it often preserves 
colours for many months, it softens and injures the tissues. 
Much can be done in special cases with glycerine, carbolized 
media, and even gelatine, but none of these media afford really 
permanent preparations which can be examined after the course 
of months or years with results much better than those obtainable 
in properly dried specimens. 
The primary causes of failure in all the foregoing cases are 
two—({1) The contractions caused by the sudden or unequal 
extraction of the water of organisation and of the cell-sap; and 
(2) chemical and physical changes in the soluble cell-contents 
and protoplasm, involving not only loss of colour but many more 
tory worker, and I would strongly urge their adoption by collectors 
who wish to have their material properly preserved for subse- 
* See Lutz, Bull. Soc. Mycol. de Fr., T. XVil., IQOI, p. 302. 
