THE STRUCTURE OF PROTOPLASM 243 



When the protoplasm is under tension, as when formed into a 

 thread or when streaming, the emulsion assumes a striated 

 appearance due to a parallel arrangement of the now elongated 

 and illuminated emulsion globules (Fig. 121a). Under stress, 

 the globules become distorted into rods which are oriented end 

 to end, sometimes so close as to appear to form a continuous 

 thread (Fig. 1216). This structure, first brought out in detail 

 and with strong contrast by the Spierer lens, had been previously 

 revealed, though less distinctly so, by ordinary (light-field) 



Fici. 12 J. -The striated structure of tlu- fine protoplasmic emulsion in a 

 Spirogyra pell. Note the delicate lines between the large bands of the spiral 

 chromatophore. The structure of the protoplasm appears to be that of threads, 

 but the threads are broken as in Fig. 119a. {From George Scarth.) 



methods. A photograph by Scarth shows the same structure 

 in the streaming protoplasm of Spirogyra (Fig. 122). 



While "dispersed phase" and "dispersion medium" would be 

 sufficient to designate the phases of this emulsion, yet it seems 

 worth while, if for no other reason than to be certain that they 

 will be "definitely reckoned with," to give Greek names to the 

 parts of this delicate visible protoplasmic emulsion. The 

 brightly illuminated dispersed phase of the fine emulsion may be 

 termed phaneroplasm (phaneros, evident), and the invisible, 

 optically empty background, or continuous phase, cryptoplasm 

 {cryptos, hidden). 



The more closely one approaches the ultimate structure of 

 protoplasm the less easy it is to differentiate vitally between the 

 relative importance of its constituents, bvit if we attempt to 



