1896.] MICROSCOPICAL JOURNAL. 131 



Special Staining Methods in Microscopy, Relative to Animal 

 Tissues and Cells. 



3. The Specific Staining OF Smooth-Musle Fibres. By 

 Dr. p. G. Unna, Hamburg. Translated from the Ger- 

 man by Geo. W. Cale, M. D., F. R. M. S. (London), St. 

 Louis. 



The smooth-muscle fibres are in general easily recog- 

 nized in the skin without specific stain. The thickest 

 series of layers, much longer, clearer, almost structure- 

 less spindles with long, little stafF-like nuclei to larger 

 spindle or ribbon-formed, give the characteristic picture 

 of the smooth-muscle as well in a longitudinal as in a 

 cross section, which should not be confused with the be- 

 fore mentioned longitudinal and cross sections of adjacent 

 normal collagen bundles. Add to this, that the usual 

 nuclear stains (hffiraatoxylin, picro-carmine) show the 

 smooth-muscle plainly, even when markedly carried-out 

 shading of the colors do not show sharply (gray-blue and 

 yellow against bluish-white and red), so that up to this 

 time there appeared no necessity for a sharper characteri- 

 zation of skin muscles. 



But for all the more difficult problems another specific 

 staining method must be sought for these parts of the 

 skin. As such I will mention, for examjjle, for the nor- 

 mal anatomy of the skin, the questionable existence of 

 the smooth-muscle fibres in the middle layer of the hair 

 follicle, in the walls of the cutaneous vessels, and the 

 demonstration of the musculature of the sweat coils, for 

 the differentiation of the smooth-muscle and connective 

 tissue fibres on the inside of the walls of hypertrophic 

 and atrophic sub-cutaneous vessels, as well as myomata, 

 certain neuromata (painful tubercles) and uevi. But when 

 it is necessary to employ such methods for such disputed 

 questions, there can be no reason why they should not be 

 used in all instances, especially in such cases in which the 



