50 



E. J. LUND 



3 ^^ 



5 10 



// 



B 



4^ 5^6^ 7i 9 lO^lli 



Fig. 8 Analysis of curves A and B of Experiment XXVII, figure 7. I, curve 



A, course of complete extrusion of ink from vacuoles containing only ink; curve 



B, course of complete digestion of extracted yolk in vacuoles containing only 

 yolk, of the same individuals used in curve A. II, Curve A, course of complete 

 extrusion of ink from vacuoles containing both ink and extracted yolk; curve 

 B, course of complete digestion of extracted yolk from the same vacuoles in the 

 same individuals as in curve A. 



We may plot the curve of extrusion of ink in group I, and 

 the curve of complete digestion of the same individuals. The 

 curves are given in figure 8, /. The same was likewise done 

 for Group II (fig. 8, //). 



Curve A of figure 8, /, (ink and yolk in separate vacuoles) 

 shows now only one early extrusion maximum instead of two. 

 Curve B of figure 8, /, is lower (owing to the smaller number of 

 individuals) but exactly similar to B of figure 7. The extrusion 

 of ink from a cell which has its yolk and ink in separate vacuoles 

 is therefore independent of the presence of food and occurs a 

 long time before digestion of the food is completed. The curve 

 of extrusion of ink, .4, figure 8, //, shows now only one maxi- 

 mum and this corresponds to the second maximum of curve A, 

 figure 7, and is practically identical with curve B of complete 

 digestion. This shows then that whenever ink is included with 

 food in the same vacuole it is retained until its accompanying 



