STAINING, PRACTICAL AND THEORETICAL 



6. Pour off excess iodine and immerse in the sodium thio- 

 sulphate solution for three minutes. 



7. Rinse in tap water ; then immerse in the potassium perman- 

 ganate solution for three minutes. 



8. Rinse in tap water. 



9. Immerse in the oxalic acid solution for five minutes. 



10. Wash in running tap water for ten minutes. 



1 1 . Immerse in three changes of distilled water for three or four 

 minutes in each. 



12. Stain in an oven for five minutes with the lithium silver 

 solution heated to 50° C. 



13. Rinse the slide back and front with distilled water to remove 

 all traces of excess lithium silver. 



14. Immerse slide in ajar of 1% formalin. 



15. Rinse both sides of the slide with distilled water to remove 

 all traces of the formalin solution. 



16. Immerse in the yellow gold chloride solution in a Coplin 

 staining jar for ten minutes. 



17. Rinse both sides of the slide with distilled water to remove 

 all traces of excess gold chloride. 



18. Flood the slides with oxalic acid and allow this reagent to 

 act for ten minutes. 



19. Rinse in distilled water. 



20. Flood the sections with the sodium thiosulphate solution 

 changing the solution every time it becomes turbid over a period 

 of ten minutes. 



21. Wash well in running water; then drain. 



22. Dehydrate in ascending grades of alcohol, clear in xylol and 

 mount. 



Results: 



Collagen is stained a reddish purple, while reticulum appears as 

 black threads. 



Reference: Laidlaw, G. F. (1929). 



268 



