OUTLINES OF BOTANY. ll 



230. To dry specimens, they are laid flat between several sheets of bibu- 

 lous paper, and subjected to pressure. The paper is subsequently changed 

 at intervals, until they are dry. 



231. In laying out the specimen, care should be taken to preserve the 

 natural position of the parts as far as consistent with the laying flat. In 

 general, if the specimen is fresh and not very slender, it may be simply laid 

 on the lower sheet holding it by the stalk and drawing it slightly down- 

 wards; then, as the upper sheet is laid over, if it be slightly drawn down- 

 wards as it is pressed down, it will be found, after a few trials, that the 

 specimen will have retained a natural form with very little trouble. If the 

 specimen has been gathered long enough to have become flaccid, it will re- 

 quire more care in laying the leaves flat and giving the parts their proper 

 direction. Specimens kept in tin boxes, will also often have taken unna- 

 tural bends which will require to be corrected. 



232. If the specimen is very bushy, some branches must be thinned 

 out, but always so as to show where they have been. If any part, such as 

 the head of a Thistle, the stem of an Orobanohe, or the bulb of a Lily, be 

 very thick, a portion of what is to be the under side of the specimen may 

 be sliced off. Some thick specimens may be split from top to bottom before 

 drying. 



233. If the specimen be succulent or tenacious of life, such as a Sedum 

 or an Orchis, it may be dipped in boiling water all but the flowers. This 

 will kill the plant at once, and enable it to be dried rapidly, losing less of 

 its colour or foliage than would otherwise be the case. Dipping in boiling 

 water is also useful in the case of Heaths and other plants which are apt 

 to shed their leaves during the process of drying. 



234. Plants with very delicate corollas may be placed between single 

 leaves of very thin unglazed tissue-paper. In shifting these plants into dry 

 paper the tissue-paper is not to be removed, but lifted with its contents on 

 to the dry paper. 



235. The number of sheets of paper to be placed between each specimen 

 or sheet of specimens, will depend, on the one hand, on the thickness and 

 humidity of the specimens ; on the other hand, on the quantity and 

 quality of the paper one has at command. The more and the better the 

 paper, the less frequently will it be necessary to change it, and the sooner 

 the plants will dry. The paper ought to be coarse, stout, and unsized. 

 Common blotting-paper is much too tender. 



236. Care must be taken that the paper used is well- dried. If it be 

 likewise hot, all the better ; but it must then be very dry ; and wet plants 

 put into hot paper will require changing very soon, to prevent their turning 

 black, for hot damp without ventilation produces fermentation, and spoils 

 the specimens. 



237. For pressing plants, various more or less complicated and costly 

 presses are made. None is better than a pair of boards the size of the 

 paper, and a stone or other heavy weight upon them if at home, or a pair 

 of strong leather straps round them if travelling. Each of these boards 

 should be double, that is, made of two layers of thin boards, the opposite 

 way of the grain, and joined together by a row of clenched brads round the 

 edge, without glue. Such boards, in deal, rather less than half an inch 

 thick (each layer about 2| lines) will be found light and durable. 



238. It is useful also to have extra boards or pasteboards the size of the 

 paper, to separate thick plants from thin ones, wet ones from those nearly 



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