BOTANICAL GAZETTE. 205 



important, only certain portions (say the bast) will have appropriated it, leav- 

 ing the other from or almost free from any stain, white as when it left the 

 Labarraque, almost. This then is an important point: the other anatomical 

 elements are free to take another color without a dauby tinge which suggests 

 bad workmanship. 



I never am in a hurry to get it out of the iodine-green. Let it have time, 

 and if required, add a few drops more of the dye. When, however, it is 

 ready, I place down small porcelain saucers, or watch crystals, in the follow- 

 ing order: to begin on my left hand, i water, 2 ammonia carmine, 3 alcohol, 

 4 alcohol, 5 alcohol, 6 alcohol pure, 7 oil of cloves. Then I take the specimen 

 from the iodine-green, dip it a moment m wa'er, then about 20 seconds to a 

 minute in the carmme, then through the alcohols, in each of which it remains 

 10 to 20 minutes, except in the first where it remains only long enough to have 

 the unfixed carmine washed away. 



From the last alcohol (which should be if possible absolute) it goes into oil 

 of cloves where it should remain long enough to become perfecdy transparent. 

 Five minutes may suffice for this, or it may require hours. 



From oil of cloves I mount it permanently in balsam. If however, any 

 water remains m the specimen it will be found that it will cloud when it is 

 placed in the balsam. Hence, as you value a nice, clear specimen, give it 

 time in alcohol and in oil of cloves. 



There are other ways than the one I have given to stain and double stain. 

 But knowing the one, others will readily enough suggest themselves. Other 

 colors too may be used, but these will do to start with. Particular objects 

 may require particular dyes. 



Thus on the same slide, I have 3 sections of Peziza floccosa. One is un- 

 stained and so transparent that it requires nice manipulation (in the balsam 

 mount) to bring out either asci or spores. The next is stained with the 

 haematoxylin dye and shows the hyphae and the root-like hairs beautifully, but 

 the asci and spores only tolerably. The third section is stained with a solution 

 of iodine-green. This developes the spores and asci strikingly and leaves the 

 hyphfe proper uncolored. 



Of course this illustration only points a general principle. I would, how- 

 ever, add that so far as my somewhat limited experience in making sections 

 of fungi goes, I have found nothing which is more satisfactory for bringing 

 out the spores than this iodine-green. 



It may be well to say in conclusion that even the advanced investigator will 

 will find these stained slides of great service to him, as the dyes act so un- 

 erringly that often a stray cell or clump of cells of a different morphological 



