328 E. T. Bell, 



condition may not differ essentially from those of a very fat individual. 

 No particular differences were noted between the muscle liposomes 

 of steers, in which the subcutaneous fatty layer was 6 cm thick, and those 

 of steers in which this layer was only 5 mm thick. It was also noted in 

 rats and dogs that excessive amounts of connective tissue fat are not 

 coordinated with excessive development of the liposomes. 



It is however clear from the above-described disappearance of 

 the liposomes during inanition that they consist of some form of reserve 

 food substance. This conclusion is in accord with the view that they 

 consist of true fats or fat-like substances. The gradual decrease in the 

 refractive power and staining-intensity of the liposomes indicates that 

 the fats are mixed in the liposome with some substance other than fat. 



The seasonal changes that occur in the musculature of the frog 

 are given separate consideration since they are not due to starvation 

 tho they present a strikingly similar picture. Fig. 1 is from the gastroc- 

 nemius of a frog (Rana pipiens) killed May 12, 1910. All the fibers are 

 full of granules. The dark fibers may be distinguished by their coarser, 

 more deeply-staining granules. All the large granules and many of 

 the smaller ones may be stained with osmic acid-the intensity of the 

 stain being greater on the larger droplets. Several other frogs killed about 

 the same time show the liposomes developed to about the same extent 

 as shown in fig. 1. 



Some control frogs of this same group were kept in the labora- 

 tory without food until June 14 — 33 days later. Fig. 2 shows a section 

 of the gastrocnemius of one of these animals, stained with Herxheimer's 

 solution. The muscle fibers are much smaller than in the May specimen. 

 This frog lost 20 per cent in weight during the 33 days. The liposomes 

 are fewer, usually smaller, and they stain much less intensely. They 

 are all faintly-refractive, and none of them can be stained with osmic 

 acid. These changes were at first attributed to starvation; but it was 

 found that frogs caught in the open showed a similar disappearance of 

 the liposomes at this season. At the present time, Oct. 1, 1910, the lipo- 

 somes have again become refractive and most of them stain brown with 

 osmic acid. They are not nearly so large and deeply-staining, however, 

 as those shown in fig. 1. 



