J. W. GROVES ON SECTIONS OF ANIMAL TISSUES. 247 



To summarise the whole of this paper :— 



1. Let the material be quite fresh. 



2. a. Take care that the hardening or softening fluid is not too 



strong. 



b. Use a large bulk of fluid in proportion to the material. 



c. Change the fluid frequently. 



d. If freezing be employed, take care that the specimen is 



thoroughly frozen. 



3. a. Always use a sharp razor. 



b. Take it with one diagonal sweep through the material. 



c. Make the sections as thin as possible, and 



d. Remove each one as soon as cut, for if sections accumu- 



late on the knife or razor, they are sure to get torn. 



4. a. Do not be in a hurry to stain, but 



b. Remember that a weak colouring solution permeates the 



section better, and produces the best results ; and 



c. That the thinner the section is, the better it will take the 



stains. 



5. a. Always use glass slips and covers free from scratches and 



bubbles, and chemically clean. 



b. Never use any but extra thin circular covers, so that the 



specimens may be used with high powers. 



c. Always use cold preservatives, except in the case of 



glycerine jelly, and never use warmth to hasten the 

 drying of balsam or dammar, but run a ring of cement 

 round the cover. 



6. Label the specimens correctly, and keep them on the flat and 



in the dark. 



