OF THE HERBARIUM. 177 



it should be uniform in size and appearance. The kind 

 that I have always used is a stout light brown material, 

 much employed in packing; it measures seventeen inches 

 by twelve ; the white paper on which the specimens lie, 

 measures fifteen inches by nine. This is quite the largest 

 size. I would recommend; anything wider or longer than 

 this becomes cumbersome and difficult to manipulate ; in 

 fact, a size smaller would probably be quite as efficient. 

 In any case, whatever form or size is adopted, let not the 

 student, from any motives of economy, employ too cheap a 

 wrapper : above all, let him avoid the thin gray and blue 

 sorts, so much used on the Continent, and frequently 

 imported into England with foreign herbaria. (In Germany 

 it is known as < Fliesspapier.') The innumerable hollows 

 arising from the inequalities of surface in cheap papers 

 invite colonies of insects to take up their abode ; while, 

 from their rough uneven nature, it is impossible to eject the 

 'voracious crew ' from their head-quarters, when once they 

 have established themselves. Another objection to a too 

 flimsy wrapper is its great flexibility, and the consequent 

 injury likely to accrue to the enclosed specimen, every time 

 it is handled. J 



We will now suppose the plants to be laid, each species 

 by itself, on their half sheets of white paper, and these 

 again slipped within the fold of their wrappers, the opening 

 of the wrapper looking to the left hand. If the examples' 

 of any given species are numerous, representing varieties, 

 abnormal forms, or growths from different localities, they 

 must be laid on separate white sheets, but enclosed in a 

 single wrapper. In all cases, however, the wrapper must be 

 confined to one species, or section of a species, if, as is often 

 the case, the latter is subdivided. This last suggestion 

 must be carefully attended to ; otherwise the arrangement 

 of the herbarium will be constantly interfered with ; besides, 

 there is a great danger of the tickets being transposed from 

 one species to another, whenever the wrapper is opened for 



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