196 THE ORCHID REVIEW. [Aucust, 1916 
though it should be as a temporary expedient. Its great drawback is that 
it usually separates allied genera and species, so that for serious work a 
more natural system is generally adopted. The genera Aganisia and 
Zygopetalum afford a good illustration, for the two are intimately allied, 
and yet they are separated by the whole extent of the alphabet. 
Similar considerations apply in the case of species, and for purposes of 
comparison it is of the utmost importance to have the allied species of a 
large genus together, not scattered over several shelves according to the 
exigencies of an alphabetical arrangement. One may receive a Masdevallia 
for name, and see in a moment that it belongs to the section Saccolabiata, 
and if these are together and arranged according to a natural sequence it 
becomes an easy matter to compare the specimen without being distracted 
by the numerous species of other sections, besides the saving of time in 
going through one instead of a dozen or more covers. Completeness is 
another important consideration. Some species of the section may be 
missing, but if each is represented by a sheet on which the name, reference, 
native country, and affinity are written one can see at once where to look 
when any specimen cannot be matched. On the other hand, species that 
may not have been named and described will be in their proper place 
awaiting the time when they can be dealt with. A useful motto for 
classification would be, ‘‘A sheet for everything and es in its 
place.” 
In a large and intricate group like Orchids the work entails constant 
and almost undivided attention, and none but the experienced can realise 
the difficulties involved, hence a little not unnatural resentment against the 
action of Reichenbach in sealing up his Herbarium against his contem- 
poraries and successors for a period of a quarter of a century; and the 
difficulty is often aggravated by the absence of dimensions from the 
descriptions, and other imperfections, which render many of them. unintel- 
ligible as a method of identification, hence the importance of being able to 
consult the specimens themselves. The Herbarium of his successor, Dr. 
Lindley, is constantly accessible, and the significance of the fact may be 
seen in an article on Epidendrum lividum on page 197. We have not yet 
had an opportunity of testing Reichenbach’s Herbarium in the same way; 
It is an apt illustration of the utility of Herbaria, and, incidentally, of the 
need for some organisation for protecting them from abuse, but this is 
outside the scope of the present article. 
The importance of a Herbarium consists largely in the fact as it 
becomes a standard of reference, and its utility constantly increases with 
the addition of fresh materials. Its value is proportionate to the complete- 
ness of its contents and the accuracy with which they are named. It 
should contain examples of every described species, and as new species are 
