&• 



LIME AND MAGNESIA. f>5 



gradual and stead}- decrease of magnesia. This decrease of magnesia, 

 compared with the increase of lime, is very significant and instructive. 68 



PROPORTIONS OF LIME AND MAGNESIA IN ANIMAL ORGANISMS. 



The muscle fibrillar of the mammalia are made up principally of the 

 contractile substance, or, as Kupffer has called it, the dynamoplast. The 

 energide (the nucleus with its connected cytoplasm), which manufac- 

 tures the fibrillar occupies but a small volume within the dynamoplast, 

 hence the writer's hypothesis would suggest the inference that the 

 lime content of muscular masses should be less than that of glandu- 

 lar masses, since the relative mass of the nucleus in muscles is much 

 smaller than in glands. From Katz's analyses the following data will 

 show how far this view is confirmed. 6 



There were found in 1,000 parts of fresh muscle of a — 



Part calcium. 



Dog 0. 0685 



Hog 0806 



Deer 0959 



Cat 0846 



Man 0748 



or an average of 0.0809 part calcium. On the other hand, Oidtman c 

 found in the liver, the largest gland in mammalia, 0.284 part of cal- 

 cium for 1,000 parts, or nearly three and a half times as much as the 

 average in the muscle. 



Embryos and young animals show a higher percentage of nuclear 

 mass in the muscles than do full-grown animals, hence the fact that the 

 muscles of the calf contain more lime than those of the cow d is in full 

 accord with the writer's inference. Zoologists have further observed 

 that the muscles of fishes and batrachia are relatively richer in nuclear 

 mass than are those of mammalia. The fact that Katz* has found two 

 to three times as much lime in the muscles of such animals as in those of 



" It may be pointed out here that lime compounds also play an important role in 

 the coagulation of the blood, as this can be prevented by the addition of some soluble 

 oxalate. Myosin, which possibly plays a part in the coagulation of the muscular 

 plasm, also contains lime. Moreover, the actions of rennet and of pectase are con- 

 nected with the presence of lime. In the absence of lime no precipitates are formed, 

 although the chemical changes by those enzymes are not prevented. 



& Pfliiger's Arch., Vol. LXIII, p. 1. 



<" Prize Treatise, Wiirzburg, 1858. This author found 1.1 per cent inorganic sub- 

 stance in the liver, and in 100 parts of this ash 3.62 per cent of lime and 0.19 per 

 cent of magnesia. Calculating from these data, there are contained 0.2842 part of 

 calcium and 0.0125 part of magnesium in 1,000 parts of fresh liver. The amount of 

 magnesium is probably somewhat too low. 



<*The lime content of the liver cells is also larger, according to Kriiger (1895), in 

 the calf than in the cow, which suggests the necessity of further microscopic com- 

 parison as to the relative, size of the nuclei. 



« Pfliiger's Arch., Vol. LXIII, p. 1. 



26982— No. 15—03- 5 



