2. Mall’s Method for Reticulum.

1. Digest frozen sections of fresh tissue for 24 hours in a solution of Parke, Davis and Co.’s pancreatin 5 grms., soda bicarbonate 10 grms., water 100 cc.

2. Wash carefully in water.

3. Place section in test-tube half-full of water and shake thoroughly to remove cells.

4. Spread out on slide and allow to dry.

5. Allow a few drops of the following solution to dry on slide:—picric acid 10 grms., absolute alcohol 33 cc., water 300 cc.

6. Stain for 30 minutes in the following mixture: acid fuchsin 10 grms., absolute alcohol 33 cc., water 66 cc.

7. Wash in the picric acid solution for a second.

8. Dehydrate in absolute alcohol; xylol; balsam.

3. Unna’s Method for Collagen.