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solving one part of gelatine, broken in small pieces, in five parts of 

 boiling-hot water, in the following manner: A deep porcelain dish is 

 placed on the top of a vessel of boiling water in such a way that the 

 bottom of the dish is kept constantly immersed in the latter. The 

 proper quantity of boiling water is then poured into the dish, and the 

 gelatine is introduced by degrees and stirred about until the last 

 portion is completely dissolved. While the dish is still resting on the 

 vessel of hot water, very stout writing-paper is coated by means of a 

 brush with the warm solution of gelatine and allowed to dry. The 

 solution must be spread over the paper as thickly as possible. With 

 a solution of one ounce of gelatine in five ounces of water I generally 

 coat 34 quarto sheets of writing-paper, A stock of this paper is 

 kept constantly on hand so as to have it in readiness when it is de- 

 sired to prepare fungi for the herbarium. To use the gelatine-paper 

 both surfaces of one of the quarto sheets are moistened, and the sheet, 

 with its prepared side up, is laid on a flat dish which has been pre- 

 viously made wet. The gelatine very quickly swells up by reason of 

 the imbibed moisture and is then in a condition to adhere to the like- 

 wise moist, prepared fungus-sectiops. The paper being ready for the 

 reception of the specimen, the latter is prepared as follows: With a 

 sharp, thin knife a vertical section is made down through the toad- 

 stool so as to divide it into two equal portions. Next, from the inner 

 portion of one of the halves a thin vertical slice is removed and laid 

 upon the moist gelatine-paper. Then another specimen is taken, its 

 stipe is cut off close to the pileus, and the latter, as well as the stipe, 

 is divided vertically into two parts. Then, by means of a sharp 

 knife with a curved, blade, the greater portion of the fleshy substance 

 is removed from the under side of the divided pileus so as to leave 

 but a very thin layer, and the two portions thus treated are laid, this 

 side downward, upon the gelatine-paper. The two halves of the stipe 

 are prepared in the same way. For the sake of economy the prepa- 

 rations are laid closely side by side upon the paper, and when the 

 sheet has been filled it is ready for the press. The prepared sheet 

 is then underlaid and overlaid with six or eight sheets of bibulous 

 white paper, and on the top of the whole is placed a piece of board, 

 which is loaded with a weight of about 55 pounds. For pressing, I 

 always employ a weight and never a press. The pressure of the 

 former is continuous, while a screw-press does not act upon an ob- 

 ject which shrinks greatly in drying. I have found that for the ma- 

 jority of fungus-preparations the weight already stated ("55 pounds) 

 is most suitable. -At the end of 24 hours the driers are to be changed. 

 On carefully removing the under dryer from the surface of the prep- 

 arations these will be found already fast adherent to the gelatine- 

 paper, although the free portions of the latter do not stick to the 

 dryer. After substituting dry sheets of paper for the damp ones, 

 the whole is submitted to pressure as before. After three or four 

 changes, and also at the end of the same number of days, the prepa- 

 tions will be thoroughly dry. Fungi which contain a large amount 

 of moisture would better be changed the first time at the end of 

 twelve hours. Preparations made on successive days, must, when 

 placed under the same press, be separated from each other by thick 



