18 



in groups of three at 120 degree angles, that the cells average 

 six sides in section and fourteen altogether in response to the 

 principle of minimal areas. 



Drops of dilute india ink on gelatine covered plates diffuse 

 in all directions giving a variety of patterns which also simulate 

 organic forms. By placing two drops side by side and a more 

 concentrated one between them imitations of nuclear divisions 

 in various stages, showing asters, spindles, centrosomes, and 

 chromosomes may be obtained. 



The Pennsylvania State College 

 State College Pennsylvania 



LITERATURE CITED 

 Gebhardt, W. 1912. Die Hauptzuge der Pigmentverteilung im Schmetter- 



lingsfliigel in Lichte der Liesegangschen Niederschliige in Kolloidalen. 



Ver. d. Deutsch. Zool. Ges. 179. 

 KusTER, E. 1913. tJber Zonenbildung in Kolloidalen medien. Jena. Ill p. 

 Leduc, S. 1912. Das Leben in seinem physikalish chemischen zusammenhang. 



Halle. 232 p. 

 LiESEGANG, R. E. 1911. Nachahmung von Lebensvorgangen. I, II. Arch. f. 



Entwicklungsmechanic. 32, 636. 



Description of Pl.\te 



Fig. 1. Imitations of fleshy fungi produced in crystalline solutions. The 

 enlargements at the tips appeared when the mixture was diluted. 



Fig. 2. Test tube preparation. The same substances were used but in more 

 concentrated mixtures. 



Fig. 3 and 5. Imitations of fern like growths crystallized from solutions 

 of Ammonium and Sodium chlorides. 



Fig. 4. Preparation made in the exhibition jar shown in the text figure. 



