The Interstitial Granules of Striated Muscle etc. 337 



sity. b) A rat was starved until it had lost 31 per cent of its body weight. 

 Microscopic examination showed a complete absence of all the muscle 

 Uposomes. The connective tissue fat was practically all removed. 

 A large part of the musculature was carefully freed from connective 

 tissue and extracted as above. This muscle was as nearly a microscopically 

 fat-free tissue as it is possible to obtain. The ether extract amounted to 

 about 0.2 per cent of the dry substance. The extract clung to the sides 

 of the flask and was oily when melted. Cover glass smears showed a 

 large number of crystals. Osmic acid colored the smears a light grey. 

 The extract presumably consisted mainly of fats solid at ordinary 

 temperatures^). The olein seems to have been almost entirely removed. 



The muscles as a place for the storage of fats. The feeding experiments 

 with rats have shown that when the animal is heavily fed for a week or 

 longer on fat meat, an unusually large amount of fat is deposited in its 

 muscle fibers. All the muscle fibers become filled with liposomes that 

 are readily stained. In two rats the fat in the muscle fibers must have 

 been quantitatively greater than that in the connective tissues. It has 

 been pointed out that the intramuscular fat is rapidly removed when the 

 animal is deprived of food. It is clear that in the rat the muscle fibers 

 have a much more important role in the storage of fats than has hitherto 

 been attributed to them. It is well known that the muscle fibers of the 

 frog are very important organs for the storage of fat. 



Relation of the liposomes to the quality of the food. When a frog is 

 heavily fed on olive oil, or fat meat, the muscle fibers become filled with 

 liposomes, tho the animal does not increase in weight appreciably. 

 Frogs fed on lean meat, grape sugar, or starch show no changes in the 

 liposomes. It is apparent that in the frog there is a close relation between 

 the quality of the food and the development of the liposomes, tho, of 

 course, factors other than the quality of the food may influence them. 



The excessive development of the hposomes in rats fed on a fat 

 meat diet indicates that in the rat also there is a close relation between 

 the amount of fat in the food and the development of the liposomes. 



^) The quantity of the extract was so small that no farther tests could 

 be made. 



Internationale Monatsschrift f. Anat. u. Phys. XXVIII. 22 



