DS 21.12-DS 21.13 DYE STAINS OF SPECIAL APPLICATION 387 



method: [whole embryos]—* running water, 24 hrs. — » 70% ale, till saturated-^ A, 

 24 hrs. — > B, till no more color comes away — * C, till dehydrated — > salicylic balsam, 

 via benzene or [(large embryos) -^ D, till cleared] 



RECOMMENDED FOR: Cartilage in wholemounts. 



note: Mercuric-fixed embryos, perfectly washed, are best. Picric-fixed material is 

 worthless. A detailed description of the application of this stain is given under DS 

 21.10 above. Miller 1921 (7()3, 20:415) first bleaches in alcoholic peroxide and u.ses 

 specially purified alcoliol. 



21.12 Williams 1941 see DS 21.11 Williams 1941 



21.13 ELASTIC FIBERS 



Much attention lias been paid to the differential staining of elastic elements. Most 

 of the techniques rely on the mordanting power of resorcinol, to which attention was 

 originally drawn by Weigert in 1898. These methods stain even the finest fibers of elas- 

 tic tissue a relatively dense black, and are thus primarily intended for the display of in- 

 dividual elastic fibers running through cartilage and similar structures. The technique 

 of Krajian 1934, on the contrary, is designed to distinguish large masses of elastic tissue 

 from other connective tissues through the differential staining of the elastic fibers in 

 red against blue. The early method of Pfitzner 1887 also deserves retention, since it 

 can be employed after chrome fixatives, when resorcinol techniques do not take well. 

 The method of Pasini (1928) (Chapter 20, DS 12.32) is also used for this purpose, par- 

 ticularly in the sections destined for class demonstration, though the differentiation of 

 fibers is not as good as the methods here given. 



21.13 Argaud 1923 6630, 891 :373 

 formula: 95% ale. 100, orcein to sat, hydrochloric acid 5 



method: [sections] -^ 95% ale. -^ stain, few moments — * abs. ale, wash-^ balsam, via 

 xylene 



21.13 Delamare 1905 see DS 13.7 Delamare 1905 



21.13 Fraenkel lest. 1928 Schmorl Schmorl 1928, 70 



STOCK solution: 95 %o ale. 60, water 30, nitric acid 3, orcein 0.75 

 reagents required: A. 3% nitric acid 90, stock 10; B. DS 12.211 Cajal 1895; C. 3.5% 



acetic acid 

 method: [sections] -^ water ^80% ale, till differentiated -^ B, 10-15 min. -^ C, rinse 



— » 95% ale., rinse -^ abs. ale. — > balsam via xylene 



21.13 French 1929 20540b, 4:11 



formula of dry stock: water 100, crystal violet 0.5, magenta 0.5, dextrin 0.25, resor- 

 cinol 2, 30% ferric chloride 12.5 

 preparation of dry stock: Boil together everything except the ferric chloride which 

 is added to boiling solution. Continue boiling 2-5 minutes. Cool. Filter. Wash and dry 



PPt- 

 FORMULA OF WORKING SOLUTION: 95% alcohol 100, dry stock 3, hydrochloric acid 2 



preparation of WORKING SOLUTION: Boil the powder 5 minutes in ale. Cool. Filter. Add 

 acid and make up to 100 with ale. 



method: [sections]^ water -> stain 3-^ to 3 hrs. ^ 95% ale. till differentiated-* bal- 

 sam, via usual reagents 



result: elastin, dark bluish green. 



21.13 French 1940 see DS 22.4 French 1940 



21.13 Gallego-Garcia 1936 tcsl. 1936 Findlay 11360, 56:160 



REAGENTS REQUIRED: ^4. 0.5% anillii blue; B.\% eosin Y 



method: [frozen sections of formaldehyde material]-^ A, 10 niins. -^ wash — > B, 10 

 mins., wash^ M 11.1 Apathy 1892 



