176 PHYSICAL CHEMISTRY 



The osmotic pressure of the blood of warm blooded animals 

 is about eight atmospheres, about as constant as the body tem- 

 perature. As we descend in the animal kingdom the osmotic 

 pressure of the blood is more and more influenced by the water 

 the animal drinks or lives in, reptiles, amphibians, bony fish, and 

 all air and fresh water animals, being more or less independent 

 of the medium. The osmotic pressure of the blood of all other 

 marine animals is the same as that of the sea in which they live. 

 The following table gives the freezing point lowering of the 

 blood (or of some fluid approximately isotonic with the blood) 

 of a number of animals : 



MAMMALS A degrees 



Man, serum 56 (,48-.62) (In cardiac insufficiency 



up to 1.099) 



Ox SS (-S3--66) 



Horse 564 



Pig 615 



'Rabbit 592 



Dog 57i (.56:62) 



Cat 638 



Sheep 619 



Whales, Mood 65-7 



BIRDS 



Fowl 6-.64 



Goose SS 



REPTILES' 



Caretta, caretta, marine 61-.69 



Colpochelys kempi, " 70 



Ghelonia mydas, " 675 



Chelonia caouana, " 602 



Emys europaea, fresh water 474 (.46- .65) 



Pseudemys elegans 48 



AMPHIBIA 



Rana esculenta 46S-S6 



Bufo viridis 76 



Salamandra maculata 479 



TELEOSTS (bony fishes) 



Charax puntazzo, marine 1.04 



Cherna gigas, " i'.035 



Crenilabrus parvo, " 75 



Box salpa, " 85 



Pleuronectes platessa, " 65-.8S 



Amia calva, land locked 508 



Anguilla vulgaris, fresh water... .S8-.69 

 Barbus fluviatilis, " ... .48-.S6 



Ca'tostomus teres, " ... -SI--S2 



ILeuciscus dobula, " ... 45 



Perca, Cyprinus, Tinea, Esox," . . . .512 

 Perca fluviatilis, " • • ■ -S--5I 



Salmo trutta and alpinus, " ... .62 



