248 



PHYSIOLOGICAL REGULATIONS 



of various tissues are modified disproportionately, some inkling of 

 their increased functional incompatibility can be visualized. 



In cases where individual frogs are analyzed, it is found that 

 tissues of one kind vary among them no more than in mammals. 

 Both in deficits and in excesses the blood shows the largest varia- 

 tion among individuals. 



The distribution of water loads can be partially visualized, re- 

 vealing characterizations sufficient to identify a precise state of 

 water load (fig. 132) even if the total water load had not been 

 measured. Thus, the mean dilution of muscle of + 22AE corre- 

 sponds to a mean increment in body of + 32AW. Using the rela- 



TABLE 27 



Increments in dilutions of tissues, in per cent of Eq, in frogs having diverse water loads. 



Coefficients of variation (C.V.) are a/control dilutions. A/ S -reciprocal 



of increment in specific gravity 



tion conversely, I find that a body of + 27AW furnishes muscles of 

 -f 19AE, as it actually did in the study of recovery from water 

 excess by isolated muscles (fig. 98). 



The frog, therefore, differs from dog and man in the greater 

 distensibility of its extracellular fluid volume. Each correlative of 

 water load is, however, just as invariably related with water con- 

 tent in frog as in mammal. 



§ 90. Rabbit 



The compositions of various tissues are measured in water ex- 

 cesses under two conditions : during life in biopsy samples of blood 

 and of some other tissues excised under local anesthesia, and at 

 sudden death. Two types of water excess prevailed; the single 

 administration of water by stomach, and the repeated administra- 



