EFFECTS OF INANITION UPON ORGANS OF RAT 89 



per cent of dry substance. (This would probably be slightly 

 higher than the dry content of the cartilaginous skeleton, how- 

 ever, on account of the higher percentage of water in the liga- 

 ments.) Further data are necessary before final conclusions can 

 be reached, but it appears that in the rat (as in other animals) 

 the percentage of water in the skeleton is increased during 

 inanition. 



It is a well known fact that in general the skeleton loses com- 

 paratively little during inanition, and thus increases greatly in 

 relative (percentage) weight. In a series of six steers, the skele- 

 ton varied from 10.6 per cent of the body in a very fat animal 

 to 19.3 per cent in a thin animal. (Data from the Missouri 

 Agricultural Experiment Station.) An apparent slight loss in 

 absolute weight of the (cartilaginous?) skeleton has been ob- 

 served during inanition as follows: pigeons, by Chossat ('43), 

 3 per cent; cats, by Voit ('66), 14 per cent; little or none by 

 Sedlmair ('99) ; dogs, little or none by Voit ('05 a) and Falck 

 ('54); rabbits, little or none by Gusmitta ('84), Weiske ('95) and 

 Pfeiffer ('87). 



Since the calcified framework is but little affected in volume 

 during inanition, it is evident that there can be but little, if any, 

 loss in absolute weight of the skeleton. It is at least theoreti- 

 cally possible that there may even be a slight increase in its 

 weight, since the fat in the bone-marrow is replaced by a mucoid 

 substance (Jackson '04) presumably of higher specific gravity. 

 Examination of bones, therefore, invariably shows a marked 

 increase in water content during inanition. As Sedlmair ('99) 

 states (p. 33): "Es giebt kein einziges sicheres Beispiel fiir einen 

 geringeren Wassergehalt der Knochen hungernder Tiere; alle 

 Forscher (Chossat und Lukjanow an Tauben, Gusmitta, C. 

 Voit und Schondorff an Hunden, Weiske an Kaninchen) fanden 

 darin einen hoheren Wassergehalt." This would naturally vary 

 in different bones, and in different animals, according to the 

 relative fat content. Small animals, like the rat, have in general 

 relatively much less marrow fat than larger animals. 



