Chapter XI 



SOME OTHER CORRELATIVES OF WATER CONTENT 

 (IN OTHER SPECIES) 



§ 87. Many compositions and functions of the dog are modified 

 in water loads ; they have now been recounted. Some will next be 

 shown to change similarly in other kinds of animals as well. How 

 nearly are the modifications suffered by various mammals alike at 

 similar water loads ? Is there a combination of features that holds 

 in all species'? Existing data can decide for man, frog, rabbit, and 

 rat ; but for the major portion of the animal kingdom, ignorance of 

 these matters is almost total. 



Lest I raise hopes of being able to present a well-filled body of 

 information for even these species, I add at once that the material 

 does not cover much of the same ground in any two of them. On 

 blood of man, for instance, some thirty sorts of changes in concen- 

 tration with water increments might be described, including the 

 relations of some of them to one another. But no one change was 

 measured often enough to furnish a coefficient of correlation, nor 

 were extreme water loads studied. And, the same kinds of con- 

 centration were not measured in any species other than man except 

 dog. 



The data proper to this chapter have been analyzed just as care- 

 fully as in the previous one, but I refrain from presenting them at 

 full length. The conclusions from them are nevertheless indis- 

 pensable if general characterizations of states of water load are to 

 be drawn. 



§88. Man 



The object is to find what variables suffer modifications along 

 with water contents in man. Each such variable serves both as an 

 indicator of water load and as a security for its recovery. The 

 information available concerns chiefly volumes of distribution, 

 blood dilutions, compositions, various metabolisms, and specific 

 behaviors. 



(1) Volumes. Most of the volumes of distribution (Vd) that 

 have been measured in diverse water contents are "plasma" vol- 

 umes (brilliant vital red, trypan red; see tables 5 and 6). It is 



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