The Interstitial Granules of Striated Muscle etc. 339 



The liposomes in the fresh tissue are seldom, if ever, stained by 

 neutral red. It is incorrect to call neutral red granules liposomes. 



The muscle liposomes do not contain any fatty acids or soaps. 



The muscle liposomes are all isotropic. 



Fresh tissues must be used if all the liposomes are to be shown. 

 A great many liposomes are often missed if the tissue be first fixed in 

 formalin, alcohol, etc. Liposomes that stain with osmic acid are, how- 

 ever, only slightly affected as a rule by fixatives. 



The liposomes of rat muscle may be entirely removed by starvation, 

 and they reappear when the animal is fed. During starvation they 

 gradually decrease in size, n amber, and staining-intensity. In the frog 

 the liposomes gradually disappear in early summer and reappear in the 

 autumn. 



When a rat is heavily fed on fat meat for several days, the lipo- 

 somes are greatly increased in number. They also increase in size and 

 staining-intensity. 



When a summer frog is heavily fed on olive oil or fat meat, there 

 is a striking increase in the number, size, and staining-intensity of the 

 liposomes. Other foods (grape sugar, starch, palmitic acid, sodium 

 oleate, and lean meat) produce no changes in the liposomes. 



The extent to which the liposomes of the rat are developed depends 

 upon the quality and the quantity of the food supply. 



The liposomes first appear as faintly-refractive droplets. At this 

 stage they may be stained with Herxheimer's solution but not with osmic 

 acid. Before their final disappearance they pass thru a similar stage. 



The liposomes are probably not cell organs but merely foci where 

 fat is deposited. Some substance other than fat must be present at 

 this focus. They consist of reserve food substances mainly, at least, 

 in the form of fats. 



Some of the sarcosomes of Retzius and some of the plasmosomes 

 of Arnold may be liposomes. 



It is improbable that liposomes have any genetic connection with 

 fuchsinophile granules. 



22^ 



