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which is the least troublesome, consistently wilh a good condition of 

 the specimens when dried, and have at last settled into the custom of 

 putting an ample quantity of porous paper between the layers of spe- 

 cimens, and not changing it until the specimens have become suffi- 

 ciently dry to he taken out of press. Frequent changing of paper, 

 artificial application of heat, previous immersion in boiling water, and 

 other recommended processes, ma}- be very useful in the preservation 

 of particular species ; but they must unavoidably increase the perso- 

 nal trouble, and consume the time of the botanist ; and that, too, 

 without equivalent advantage in the case of at least ninety in the hun- 

 dred of our native species. Some practice is requisite to apportion 

 the pressure to the resistance of the paper and plants, and on the suc- 

 cess of this will materially depend the beauty of the specimens. If 

 too little pressure be applied, the specimens shrivel, and remain in- 

 conveniently brittle. If too much pressure Be used, the structure of 

 parts is rendered less fit for after examination, and the colours are de- 

 stroyed. The quantity of paper to be introduced between the layers 

 of specimens, will vary according to the nature of the plants and the 

 thickness of the paper, itself. In my own practice it ranges from 

 half a quire to many quires of demy grey, common blotting-paper, or 

 thick filtering-paper : grasses and ferns, for example, requiring much 

 less paper than do the lilies and Chenopodiums. The more common 

 faults wdth botanists, are those of giving too little pressure, and using 

 too small a quantity of paper; so that their specimens are both fra- 

 gile and bad-coloured. Heavier pressure would prevent fragility, — - 

 more paper would preserve the colours. I do not recommend my 

 own custom as being productive of superexcellent specimens, but as 

 productive of sufficiently good specimens at the smallest cost of time 

 and trouble to the botanist. And I cannot hesitate to add, after see- 

 ing the specimens of scores of other botanists, that those dried by my 

 simple and time-saving process, are considerably above the average 

 in quality, as regards both the preservation of colour, and fitness for 

 fastening on white paper. In illustration, I have used the freedom to 

 address to the Editor, a packet of specimens dried in 1841 and 1843 

 without any change of papers. They will show that the colours of 

 the Orchis, primrose, cowslip, many blue flowers, and other plants 

 which usually fail in this respect, may be well enough preserved with- 

 out any greater trouble than that of putting the plants into paper when 

 fresh, and taking them out when dried. — Hewett C. Watson ; Thames 

 Ditton, September 15, 1843. 



