SECTION TWO 



Technique: 



1. Material should be fixed in 5 or 10% formalin and embedded 

 in paraffin wax. Sections are cut 6 to 12^ in thickness. 



2. Fix sections to slides; remove paraffin wax and take down 

 to 70% alcohol by the usual stages. 



3. Pass through 30% alcohol; then stain in Solution C for five 

 minutes. 



4. Rinse in two changes of tap water. 



5. Immerse in Solution D for one to two minutes. 



6. Wash in running water for two to five minutes to remove the 

 unchanged molybdate. 



7. Dehydrate; clear in xylol and mount. 



Note: A deep yellow filter is of great help in microscopic 

 examination, although not necessary. 



Results: 



Nuclei, dark blue ; nucleoli of neurones, red ; axial substances 

 of nerve fibres, dark to pale blue ; cuticular substance (including 

 myelotheca) of nerve fibres, red ; neurilemma (of Glees), purplish 

 red. 



Note: To eliminate all myelin, sections should be passed through 

 Cellosolve after the alcohols. The same precaution should be 

 observed when preparing tissue for embedding. 



From Proceedings of the Royal Irish Academy, Vol. 53, Section B, No. i, The 

 Myelothecal Apparatus of Human Nerve; and from personal communications 

 with Professor M. A. MacConaill, m.r.i.a. 



LEISHMAN STAIN 



For general differentiation of blood corpuscles; for malarial 



parasites; trypanosomes, etc. 



This stain is extensively used by British workers who generally 

 prefer it to Wright's stain which is used extensively in America. 



Solutions required: 



A. Formol saline, neutral, buflFered. 



B. Leishman stain. 



C. Acetic acid o-o8% aqueous. 



L 135 



