264 RALPH S. LILLIE AND EARL N. JOHNSTON. 



DESCRIPTION OF PLATE II. 



FIG. 6. Fe-ferricyanide structures, on the surface of the solution. Strige about 

 50 microns apart. 



FIG. 7. Branching produced in a growing Fe-ferricyanide filament by punc- 

 turing with a finely pointed needle. In the corner is a branch formed naturally. 



FIG. 8. Branches produced by puncture in an Fe-ferricyanide filament after 

 growth had ceased. 



FIG. 9. Fe-ferricyanide filaments finely striated. Striae about 25 microns 

 apart. These filaments are on the surface of the solution. 



FIG. 10. Large Fe-ferricyanide filaments, on the surface of the solution, broken 

 up by fine particles of sand. 



