32 THE AMERICAN MONTHLY [February, 



The epidermis, hair-shaft, outer root-sheath, connective tissue, elas- 

 tic fibres, smooth and striated muscle stain yellow ; all glands, mem- 

 brane of fat cells, cartilage and nuclei stain blue. 



TRIPLE STAINING. 



Metanil Yellow, Methyl Green and Safranin. — Preparation : 

 ala nasi of a child, alcohol hardening. 



The sections are stained for 8 minutes in the yellow solution, then for 

 30 seconds in the safranin solution, then for 20 seconds in the methyl 

 green solution, and finally passed through the metanil yellow solution. 



The different elements are differentiated as in the double stain with 

 metanil yellow and methyl green, except the color is of a darker shade 

 and all muscular elements ai'e stained red. 



Metanil Yellow, Crystal Ponceau and Crystal Violet. — Prep- 

 aration : ala nasi of a child, alcohol hardening. 



The sections are stained for 2 to 16 minutes in a mixture of 5 c.c. of 

 the yellow solution, 5 c.c. of the ponceau solution, and 3 c.c. of the 

 violet solution, or they are stained for 8 minutes in the yellow solution, 

 then for 6 minutes in the ponceau solution, and finally for 15 seconds in 

 the violet solution. 



Cartilage and nuclei of cartilage cells, the superficial layer of the 

 epidermis stain blueish-violet ; connective tissue, elastic fibres and 

 glands stain light red ; the deep layer of the epidermis, the rete Mal- 

 pighi, hair-shaft, the root-sheaths, membrane of fat cells and muscle 

 stain yellow. 



Metanil Yellow, Azo Blue, and Methyl Green.— Preparation : 

 ala nasi of a child, alcohol hardening. 



The sections are stained for 10 minutes in the yellow solution, then 

 for 6 minutes in the blue solution, and then for 2 minutes in the green 

 solution ; finally the sections are passed through the yellow solution. 



The epidermis, hair-shaft, inner root-sheath, smooth and striated mus- 

 cle stain yellow ; membrane of cells, the rete Malpighi, membrana pro- 

 pia of glands, elastic fibres and connective tissue stain violet ; nuclei 

 of gland cells and nuclei of the cells of the Malpighian layer, outer root- 

 sheath, smooth muscle and connective tissue stain green. 



Crystal Ponceau, Methyl Green and Crystal Violet — Prepai-- 

 ation : ala nasi of a child, alcohol hardening. 



The sections are stained for 8 minutes in a mixture of 10 c.c. of the 

 ponceau solution, 4 c.c. of the green, and 2 c.c. of the violet, or they 

 are stained for 8 minutes in the ponceau solution, then for 3 minutes in 

 the methyl green solution, and then for 5 seconds in the violet solution. 



The epidermis, hair-shaft and outer root-sheath stain violet ; smooth 

 and striated muscle, elastic fibres and connective tissue stain rose-red ; 

 the stratum mocosum stains green ; the inner root-sheath, all glands and 

 membrane of fat cells, cartilage and nuclei of its 'cells stain green. 



QUADRUPLE STAINING. 



Metanil Yellow, Safranin, Methyl Green and Crystal Violet. 

 — Preparation : ala nasi of a child, alcohol hardening. 



The sections are stained for 20 minutes in the yellow solution, then 

 for 1 minute in the safranin solution, then again for 5 seconds in the 

 yellow solution, then for 2 minutes in the methyl green solution, then 

 again for 5 seconds in the safranin, then again for 5 seconds in the yel- 

 low solution, and finally for 10 seconds in the violet solution. 



