408 E. T. Bell. 



tioris of muscle from six or eight different parts of the body have 

 also been examined for the presence of fat. 



The muscle samples have been examined in this laboratory by 

 Mr, H. H. Bullard, who is making a special study of the musculature 

 of the ox. His observations on the fat content of the muscle fibers 

 are given below. 



Three of the animals slaughtered were very fat. One of these, a 

 well-known prize-winner in the show-ring, was three years old, and 

 had been excessively fat for over a year. The subcutaneous fat was 

 in some places over 8 cm. thick. iSTone of these animals had any 

 fat in the epithelium of the glands examined or inside the muscle 

 fibers. Fat droplets were present in the cells of the articular carti- 

 lage. 



The second group of animals, three in number, were moderately 

 fat. In two of these fat droplets were found in the hepatic cells. 

 The cartilage cells of all three contained fat droplets. 



A third group of six animals were comparatively thin — the sub- 

 cutaneous layer of fat being only a few millimeters thick. In one of 

 these some of the cortical renal tubules were full of fat droplets. The 

 cartilage cells of all contained fat. Two animals showed a consider- 

 able amount of fat in the cortical cells of the adrenal. 



A fourth group of animals were exceedingly thin, having been 

 kept on submaintenance several months. They were fed so that they 

 were made to lose weight at the rate of about half a pound a day. 

 The connective tissue fat deposits were nearly exhausted. One of 

 the animals showed a large amount of fat in the cortex of the adrenal. 

 All three show fat inside many of the muscle fibers. The cartilage 

 cells of one animal were examined and found to contain the usual 

 amount of fat. 



It appears from the above observations that in cattle nine months 

 or more old no fat is found in the salivary glands, pancreas, or 

 spleen. In the thymus fat was often found in the Hassall corpuscles. 



Fat was found in the hepatic cells in two moderately fat animals, 

 but was absent in all the others. In one of the submaintenance 

 animals the cells had shrunken to about half their normal diameter 

 and their outlines were no longer visible. It is clear that the presence 



