154 CONNECTIVE TISSUE. 



basis- substance appears indistinctly striated and granular. (See 

 Fig. 53.) 



If we expose a piece of the fresh, umbilical cord for some 

 hours to the action of a large quantity of a one-half per cent, 

 solution of chloride of gold, the specimen assumes in the daylight 

 a dark violet color. Sections exhibit branching and connecting 

 strings of dark violet color, whose nuclei at the points of inter- 

 section are either black or pale violet, while the basis-substance 

 is but faintly stained either pale violet or pink. The strings in 

 their general features and size correspond both to those seen in 

 specimens preserved in chromic acid and to the light spaces 

 found in specimens stained with silver. The pale basis-substance 



FIG. 54. UMBILICAL CORD OF A HUMAN FCETUS, NINE MONTHS OLD. 

 STAINED WITH CHLORIDE OF GOLD. 



P, dark violet bioplasson cords, corresponding to those in Fig. 52, and to the light 

 spaces in Fig. 53 ; B, pale pink basis-substance, indistinctly striated. Magnified 500 

 diameters. 



exhibits an indistinct striation, and some smaller offshoots from 

 the violet strings pass into and are lost in striated bundles. 

 (See Fig. 54.) 



By comparing the chromic-acid, the silver-stained, and the 

 gold-stained specimens, it is apparent that the light spaces are 

 identical with the violet tracts, and these again identical with 

 the bioplasson strings of the unstained specimen. In other 



