404 S. MORGULIS, PAUL E. HOWE AND P. B. HAWK. 



simply due to a qualitative transformation of the fat present in 

 the cells whereby it becomes histologically visible. Since the 

 staining reagents which are used in demonstrating the presence 

 of fat globules are such that they react only with unsaturated 

 fats, the appearance of the globules indicates that with the 

 beginning of the fast a process of desaturation and probably the 

 formation of fatty acids is started preliminary to the absorption 

 of this fat to serve the nutritional needs of the organism. 



The results of studies on fasting unicellular organisms where 

 the conditions are simpler and easier to be appreciated support 

 the view that vacuolization is one of the earliest and the most 

 common degenerative process which ensues with the exhaustion 

 of the reserves of the cell. Wallengren indeed in his most valu- 

 able research on inanition of infusoria distinguishes two periods, 

 before and after the reserve material is exhausted. The former 

 is accompanied by a gradual diminution of the animal, while in 

 the second period the endoplasm becomes honey-combed with 

 vacuoles of various sizes. 



Vacuolization has been observed in various tissues: in gangli- 

 onic cells of the heart (Statkewitch) , in the cells of the motor 

 ganglia of the anterior horn (Schaffer) in bone marrow (Soltz), 

 in the nephridial epithelium, etc. 



Before concluding the paper mention should be made of an- 

 other degenerative process which develops in the course of 

 inanition. We refer to the gradual melting away of the cell 

 boundaries which, with their complete disappearance, may even 

 result in the formation of a syncytium. One of us described 

 this condition in the liver of fasting salamanders. We also 

 observed this phenomenon in our liver and kidney preparations. 

 Similar observations have been made in fasting lower animals 

 (Schultz). In the study of the salamanders it was shown how 

 rapidly the cell walls are built up again around the intact nuclei 

 as soon as the emaciated animals are once more given food. 



At last the more or less universal loss of staining capacity due 

 to the degenerative transformation produced by inanition and 

 described by practically all authors must be pointed out. 



