16. 



comparable, tha regeneration curves being plotted ??ith ordinate as concent mtlon 

 and asscissa as time, an i tne COg cunreo being plotted with orlin its ae con- 

 centration *m ■' *o«ciBea as cc. COo as 0*01 WBSCO3, still they do serve to shoe 

 that as CO2 production is increased, regeneration is decreased progressively. 



Child (1911) has shown th-*t for pl^.naria the rate of regeneration 

 le proportional to tlM nta of met-sbolisw: and thit consequently younger or 

 entailer worms regenerate store rapiily than the larger on^s. In tadpoles, as 

 has already been pointed out, the rate of regeneration is greater in the soallsr 

 indiviiuals. The fact, then, that a decrease in regeneration is correlated 

 with a rles in carbon dioxide production in basic media must be regarded as 

 shoving tnat the increased oxygen aetabelism due to bases is a destructive 

 metabolism and not indicative Of any stimulation of tha normal functions of 

 the organ ism. 



It will be notad that in both of the above experiments (Fig. 13 

 and 15) the regeneration of tha tadpoles in watar containing ten cubic centimeters 

 of the base nvade up to 400 was better than that of the controls. It will also 

 bs seen by examination of the data (tables 9 and 10) that while the initial 

 hydrogen ion concentration of these solutions is decidedly on the basic side 

 of neutrality (P.H. aoout 9), that by the time the solution was changed, it was 

 slightly acid (P.H. about 6.3). For this reason another series of experiments 

 was planned, using- trv» saaa concentrations, but a larger volume in proportion 

 to the size of the tadpolas and changing the solution oftener. two parallel 

 eeries were run, each containing five small tadpolae in one liter of distilled 

 water, ,90025 H. EaOH ani .0005 B. HaOH(25 0.0. and 50 o.c. 0.01 ». par liter). 

 The experiments were curried out in two-quart mason jars kept tightly sealed 

 ani containing test tubes of Ba(0H) 2 solution to absorb the CO^ from the air 

 above the water. The results of this experiment are given in t-ible 13. Due 



