422 BLOOD AND GLANDS 



toluol, and mount in balsam. Cytoplasm stains blue to lilac, 

 nuclear chromatin deep red, contents of thyroid vacuoles sky 

 blue, and colloid droplets of Hiirthle deep blue to deep red. 



Williamson and Pe^rse {Journ. of Anat., Ivii, 1923, p. 193) 

 fix and mordant in a special solution made as follows : Potassium 

 bichromate 40 grm., chromium fluoride 40 grm., are dissolved by 

 boiling for half an hour in 2000 c.c. of distilled water. The solution 

 is cooled, filtered, and 100 grm. of mercuric chloride is dissolved 

 by boiling in the filtrate. Pieces less than 3 mm. in thickness are 

 fixed, hardened and mordanted in twelve hours and after washing 

 in water are imbedded in jjaraffin, celloidin, or gum. The fluid 

 may also be used as a simple mordant after formol, alcohol, or 

 osmic fixatives, but pieces must be first well washed, acetic, formic 

 and osmic acids being inimical to the mordanting. Sections are 

 brought to alcohol and Ig is used to remove crystals as well as 

 for some action which it exercises. The sections are then trans- 

 ferred to 95 per cent, alcohol for half an hour, and are then brought 

 to water where they are treated with \ per cent. KMn04 for ten 

 minutes, followed by 5 per cent, oxalic acid until just decolourised, 

 and are washed in running water for ten minutes. They are 

 then stained in Mallory's phosphotungstic hsematoxylin (§ 312) 

 for fifteen to twenty-four hours and brought to mounting after 

 washing. 



Haver {Journ. Path, and Bad., xxx, 1927, p. 621) fixes in 

 7 per cent, formol or in a mixture of formol 5, acetic acid 5, and 

 Miiller's fluid 90, and stains in a variety of stains. See also Krause 

 {Virch. Arch., ccxviii, 1914, p. 107); Severingham [Zeitschr. 

 fur Zellf, xix, 1933, p. 635). 



906. Thymus. The usual histological methods give good results. 

 For haematological studies the Maximow Zenker fixative is 

 recommended. 



Dearth {Amer. Journ. Anal., xli, 1928, p. 321) fixes in Carnoy's 

 fluid (§ 90) and stains in hsematoxylin followed by orange G or 

 picro-fuchsin. See also Salkind {Anat. Anz., xli, 1912, Nos. 6 

 and 7). 



907. Adrenals. Chromaffin tissue, Wiesel {Anat. Hefte., xix, 

 1902, p. 481) fixes one to four days in 5 j^er cent. KgCrgO^, 10 c.c. ; 

 10 per cent, formol, 20 c.c. ; distilled water, 20 c.c. Tissues are 

 then placed in 5 per cent. KgCrgO^, for one or two days, washed 

 one day in water and imbedded. Sections are stained twenty 

 minutes in 1 per cent, toluidin blue or wasserblau, washed five 

 minutes in water and stained twenty minutes in 1 per cent, 

 safranin. They are then differentiated in 95 per cent, alcohol to 

 a blue shade, then 95 per cent, alcohol, cleared in carbol xylol, 

 xylol and mounted in Canada balsam. 



In general chromaffin tissue is fixed and stained by those 

 fixatives containing chrome or osmic acid by a simple reduction 



