The Identification of Intracellular Structures. 105 



be said about fixatives at a later stage. With regard to the useful 

 manner of distinguishing between fat and yolk (lecithin) by 

 dehydrating the material to be examined in acetone, which dissolves 

 away the fat and leaves lecithin, it should be mentioned that this 

 test is not embodied in my tables because acetone is unsuitable for 

 routine dehydration work, and is scarcely ever used. The tests 

 given by me in paragraphs 3 and 4, sections h and d, work as 

 well, and can be used on material dehydrated in the more efficient 

 alcohol. I have described the modus operandi of the fixatives and 

 stains below. 



Analytical Tables of the Main Chemical and Staining 

 Tests for Cytoplasmic and Deutoplasmic Inclusions. 

 (See page 109.) 



1. Golgi Apparatus {Batonette Part, Dictyosome, Nehenkern 



Bod, Chondrioplast). 



{a) Black in Kopsch and Sjovall methods.* 



(&) Black in Golgi or Cajal's formol-silver nitrate methods, 



(c) Generally destroyed by acetic acid (circa 5-10 p.Cr) even in 



mixtures containing chrome salts and osmium tetroxide, e.g. 



riemming, 



{d) Preserved in formalin (neutral, circa 5-20 p.c.) followed 



by upgraded alcohols, xylol and wax. (But may not stain in 



hcematoxylin of Haidenhain). 

 {e) Black in Kopsch- Altmann. 

 (/) Green when stained in Janus green, 1 in 30,000, intra 



vitam. Sometimes will not stain intra vitam. 



{g) Dissolved by alcohol of 80 p.c. (Compare 3, c.) 



(h) Barely (if ever) goes black in Kopsch (OsO^) to which any 



part of chromic acid (or KaCraO;) has been added. Will not 



blacken in Flemming without acetic. (Compare 3, e.) 



2. Mitochondria (Chondriosomes, Chondriokonts, etc.). 



{a) Yellow to brownish in Kopsch ; may go black after Sjovall's 

 method, rarely black after Kopsch. 



{h) Either do not stain, or yellowish in a successful Golgi or 

 Cajal formol-silver nitrate impregnation. 



(f) Act like Golgi apparatus in acetic acid. 



{d) Act like Golgi apparatus in neutral formalin (but always 

 stain in hematoxylin of Haidenhain). 



(e) Bed to purplish in Kopsch- Altmann. 



• For these methods see page 109. 



