134 THE AMERICAN MONTHLY [April 



stance, as it is ranged next to collagen in its acidophilous 

 character, and chiefly it will not be distinguishable from 

 collagen. On this account it will be found necessary in 

 all cases, even in those in which unfortunately a strong 

 separation of collagen from smooth-muscle is sought, to 

 seriously stain in a permanent manner the elastin by 

 means of the well-known quick staining in acid orcein 

 solution. For the methods which have been given, the 

 simple methyl -blue or orcein method are not available 

 for this combinatiou, as the muscles do not assume the 

 blue color in double orcein applications. On the other 

 hand the methyl-blue-permanganate alcohol method and 

 the acid fuchsin-picric method are especially applicable. 

 In this latter combination it will be found advantageous 

 to follow the elastin staining with a hematoxylin nucleus 

 stain. Then, even if the nuclei appear red, after my sim- 

 ple acid fuchsin-picric method, they suffer somewhat from 

 a stronger picric treatment, and a hematoxylin stain im- 

 proves the sharpness of the picture materially. These 

 two methods can be supplemented any desired manner. 

 For whilst the last named four-color method is limited, 

 as for example in hypertrophic changes of vessels through 

 the sharp contrast between red, yellow and brown, very 

 marked showing with low powers, the first named two- 

 color method furnishes more transparent and better pic- 

 tures for study with higher powers ; and this the more 

 so because the contours of the elementary parts appear 

 more distinctly. 



I. Denonstration of Smooth-Muscle in Collagen. 

 (a) Metliylene-blue atid Orcein Method. 



1. Polychrome methylene-blue solution, J hour or 

 longer. 



2. Water. 



3. N. Spirituous orcein solution (1 per cent), 15 minutes. 



4. Absolute alcohol, oil, balsam. 



