78 



Comparative Animal Physiology 



least in the cockroach, ^-'^ and whether the ratio is less or greater than 1 may 

 be a genetic character. 



Many cellular functions vary with the ratio of alkaline metals to alkaline 

 earths. This ratio [(Na+K)/(Ca+Mg)] is higher in'vertebrate bloods than 

 in body fluids of invertebrate animals. ^'^ 



TABLE 9 



CONCENTRATION OF IONS IN SEA WATER AND IN BODY FLUIDS 

 For sea water, in mM/1.; in body fluids, in mM/1. (except where stated as mM/1. H:;0) 



