468 APPENDIX. 



during injection. If the specimen is large or difficult to 

 inject, the whole operation must be performed in a vessel 

 of water as hot as the hand can bear it. 



WHITE-OF-EGG INJECTION. 



Preparation. — Eub up fresh white of egg with carmine injec 

 tion, or other colouring fluid which will not cause coagu- 

 lation of the albumen. 



Use. — For injecting specimens of which sections are to be cut. 

 It is used fresh, and the specimen is then placed in 

 alcohol, or in hot water, to coagulate the albumen. 



GUM INJECTION. 



Preparation. — Make a thick mucilage of gum-arabic and cold 



water. 

 Use. — Inject cold, previously colouring as desired. Plunge 



the specimen into alcohol, and the injection will sohdify. 



