— (49— 



end of wliich time the piirailiii luny Ijl- removed as a])ove 

 described. This method is very useful for mounting serial 

 sections. 



Gaule's 50 y^ Alcohol Method. 



A few drops of 50% alroliol are i)laced on a slide or 

 cover glass; on this the sections are placed. As the alcohol 

 evaporates, the sections are fixed to the slide or cover; 

 12 to 24 hours are required, and it is best to place them in 

 a warm oven at a temperature of 40' C. The paraffin is 

 removed in the same manner as when sections are fixed 

 with albumen fixative. The slide or cover must be very 

 clean, even then the sections are often loosened while the 

 paraffin is being r(;moved. Sections from alcohol or subli- 

 mate hardened tissues seem to be most firmly fixed. 



Dextrin Method of Fixing Sections. 



This method is to be reconj mended for class purposes, 

 where 30 to 50 or even more preparations have to be stiiined 

 in section. 



The following two solutions are kept on hand: — 

 Sol. No. 1. 



A solution of equal i)arts of white sugar and 



boiling distilled water . , 300 c. c. 



A solution made with equal parts of dextrin 



and distilled water , . 100 c. c. 



Absolute alcohol . . . 200 c. c. 



Mix the sugar and dextrin solutions in a mortar, and 

 add very slowly, wliile constantly stirring, the absolute 

 alcohol. Filter through fine muslin, and keep in a wide- 

 mouthed bottle. Place in the cork a broad camel's-hair 

 brush. 



Sol. No. 2. 



c^l if Photox(})l^Jn (dry) or good celloidin or gun 



I cotton ..... 10 grms. 



Absolute alcohol ..... 100 c. c. 



Ether . 500 c. c. 



The sections to be stained are cut in paraffin, and 

 arranged on a piece of paper. A clean glass plate is coated 



