151 



formation into white indigo, takes about two hours under the 

 influence of a special ferment. u Diastase, " hydrating and oxyda- 

 ting, which exists in the cells of the leaves. The liquid is then 

 withdrawn from the warm maceration, and is cooled with cold air 

 by some mechanical means. The white indigo becomes blue indigo 

 but insoluble. By these means three times more indigo is produced 

 than by the primitive method. The indigo thus obtained is very 

 pure, and contains from 80 to 82 per cent, of indigotine, the colour- 

 ing matter of indigo. 



INSTRUCTIONS FOR DRYING PLANTS, 



Ry C. Curtis, f. l. s. 



Many readers of this Bulletin will occasionally come across a plant 

 of which they would like to know the name, and it is not so gener- 

 ally understood as it should be that in most cases plants can be as 

 easily determined from dried as living specimens. There is a story 

 told in botanical circles, of a living plant being brought to an emi- 

 nent botanist which he failed to identify, but he hinted that if it 

 were taken away and sat upon for a week he would probably be 

 able to name it. In the case of timber trees, and other large 

 growing plants, it is manifestly impossible to send specimens for 

 identification, any great distance, in any other way except dried, 

 and as there is still much to be done in collecting and determining 

 the Forest Flora of this region it is with the hope that some at 

 least of those who are living amid forests will turn their attention 

 to collecting and drying plants, that I propose giving a few hints 

 as to how to do it. A complete specimen consists of leaves, 

 flowers and fruits, and in the case of small growing plants it is 

 desirable to have the whole plant with the roots attached. Such 

 specimens are not always obtainable at the same season and in 

 that case leaves and flowers or leaves and fruits will suffice, but 

 leaf specimens alone are seldom sufficient for determination. 

 Whenever possible the specimens should be gathered dry, and if 

 wet should be laid out singly for an hour or two before putting them 

 in paper to allow the moisture to evaporate, but not long enough to 

 allow them to wilt. In the case of fleshy plants or those that dry 

 badly; thatis to say, those from which the leaves drop off even with 

 the greatest care, immersion for a few minutes in spirits of wine or 

 boiling water is a good plan. After immersion these should also 

 be laid out singly until the moisture has evaporated. 



All sorts of more or less elaborate presses have been devised for 

 drying plants, but there is nothing better than a pair of simple wood- 

 en frames as shown in the accompanying illustration, and which I 

 have used for more than twenty years. Each frame consists of 

 eight pieces of any strong light wood, three-eighths of an inch thick, 

 and two inches wide. Five of these, twenty-three inches long, are 

 placed about two inches apart and to them nailed transversely three 

 pieces twenty inches long. The drying paper, which should be of 

 an absorbent kind, (there is nothing better than blotting paper 



