R. R. Bensley 



lOl 



evaporated to dryness on a water bath under a continuous stream of carbon 

 dioxide. This extract contained, in addition to the lipids, neutral salts and 

 organic extractives. The residue was extracted with dry chloroform, filtered 

 into a small weighed flask, and evaporated to dryness in a stream of carbon 

 dioxide. The flask and contents, dried to constant weight in vacuo, gave the 

 total lipids. The fats were then dissolved in alcohol, the solution transferred 

 to a volumetric flask and diluted to volume, after which an aliquot was taken 

 for phosphorus determination, from the results of which the total phospho- 

 lipid content, estimated as lecithin, was computed. 



TABLE 1 



The phosphorus determinations were made by a modified Fiske and Subar- 

 row method, for the details of which I am indebted to Dr. Grafflin of the 

 Harvard Medical School. 



Table 1 shows the results of these analyses in three separate experiments. 



The striking feature of these analyses is the almost complete disappearance 

 of fats and phospholipids from these emulsions on long-continued centrifuga- 

 tion, indicating that these substances are associated in the intact cell with 

 stable structural elements, and are present only in traces in the intcrgranular 

 medium. 



Since the liver cell is a somewhat specialized form of the cell, a similar ex- 

 periment was carried out with the testis of the guinea pig. Four adult guinea 

 pig testes were freed from their capsules and homogenized, as described above, 

 with buffered saline. The emulsion was transferred to a 50 cc. vohmietric flask, 

 diluted to the mark, and thoroughly mixed. Twenty-five cc. were taken for 

 analyses for total fats and phospholipids and the remaining 25 cc. centrifuged 

 for 3I/2 hoias at 12,000 r.p.m. The results are expressed in table 2. 



In this experiment the loss in phospholipid content as a result of high speed 



