154 



Papers from the Department of Marine Biology. 



ency to lose their cell-wall and to become a syncytium. Usually the 

 loss of material is not nearly so selective as in the vertebrates; practi- 

 cally all organs become involved in the loss in an early stage of inanition, 

 except in forms in which there is some special storage tissue, as the fat- 

 bodies of insects. 



The much more extensive literature dealing with inanition in verte- 

 brates shows that the loss of body-substance takes place in a highly 

 selective manner, involving many tissues before any marked loss is 

 undergone by the "vital organs." Several researches in this field have 

 demonstrated the importance of metabolic muscular activity as a factor 

 in determining the rate of tissue destruction. The usual course of the 

 changes involved in inanition is not, however, greatly altered by 

 differences in the rate of metabolism, the one factor most influenced 

 being the rate of occurrence of these changes. 



TABLE 9. 



The results of three series of experiments, in each of which the halves 

 of 20 disks were prepared in such a manner that they fell into one of 

 the three categories described on pages 127 and 128, are presented in 

 tables 6, 7, and 8, and figures 10. 11, and 12. 



A summary of the results for each of the series of experiments is 

 given in their proper order in table 9, in which the weights are reduced 

 to terms of 100 grams for the original weight of each set of half-disks in 

 each series. A comparison of these tables and the curves for the loss 

 of weight with those given for the rates of regeneration under similar 

 operations show a striking similarity in the results when those obtained 

 by the use of these standards of measurement are compared, although, 

 as previously stated, the tissues chiefly concerned in the two forms of 

 metabolic activity are fundamentally different. 



Table 10 gives the record of the halves of 10 disks prepared to give 

 active and inactive specimens and shows loss in weight, decrease in 

 diameter, measured for each half-disk at the line of separation of the 

 halves, and shrinkage in the diameter of a cavity originally 22 mm. 

 In several instances the diameters of the halves of the same disk vary 

 1 to 3 mm. on account of irregularities in the outline due to the cuts 



