256 THE AMERICAN MONTHLY [Sept., 



tions in alcohol two or three times. 5. Pour off the alcohol, 

 and cover the sections with an alcoholic solution of iodine green, 

 (1 per cent) and allow to stand for 45 minutes. 6. Pour off the 

 iodine green, and again rinse the sections in about two changes 

 of alcohol, or until the carmine is clear. 7. Pour off the alcohol, 

 and cover the sections with oil of cloves, and when clear mount 

 in balsam. Borax-carmine is by far the best stain for all botan- 

 ical purposes with very few exceptions. The only other stain 

 required, is that of logwood. With these two stains and a judic- 

 ious use of hydrochloric-acid, nearly every phase of permanent 

 staining can be effected. 



TO DECOLOR AND CLARIFY. 



It is sometimes necessary to decolor tissue for the purpose of 

 showing structure that could not otherwise be seen, viz., fructi- 

 fication of ferns, mosses, capsules, etc. To do this manipulate 

 as follows: — 



1. Place the specimen as soon as possible after collecting into 

 92 per cent alcohol, and allow it to stand until the chlorophyll, 

 etc., is all extracted. 2. Pour off the alcohol, and place the 

 specimen in water to relax for about 30 minutes. 3. Pour off 

 the water, and place in potash solution, and allow to remain un- 

 til clear. 4. Pour off the potash solution, and cover with water, 

 allow it to stand for about 30 minutes, changing the water two 

 or three times. 5. Pour off the water, and cover the si)ecimen 

 with equal parts of alcohol and pure glycerine. Allow it to 

 stand for the alcohol to evaporate. By so doing the glycerine 

 will become concentrated and the tissue permeated ready 

 for mounting in either pure glycerine or glycerine-jelly. 6. If 

 it be desired to mount the object in balsam, pour off the water 

 as in 5, and cover the specimen with 92 per cent alcohol, and 

 allow to stand until dehydrated. 7. Pour off the alcohol, and 

 cover the specimen with oil of cloves, and when clear mount in 

 balsam. 



FORMULyE. 

 NO. 1. HCEMATOXYLIN (KLEINENBERG). 

 (a). Make a saturated solution of crystallized calcium chloride 

 in 70 per cent alcohol, and saturate with alum. 



(b). Make a saturated solution of alum in 70 per cent alco- 

 hol, and add one part of (a) to eight parts of (b). 



