178 



PHYSIOLOGY OF THE INVERTEBRATA. 



The nitrogen is simply dissolved in the blood, but the 

 oxygen and carbonic anhydride are partly dissolved and 

 partly in a state of loose chemical combination with certain 

 constituents of the blood. The oxygen, with the hsemocyanin, 

 and possibly the greater part of the carbonic anhydride, is 

 united to certain salts contained in the blood. 



(6) Blood of Cancer pagurus. 



The blood was obtained from very large individuals by 

 opening the carapace, and passing the capillary point of the 

 canula directly into the heart. 



A hundred volumes of the blood yielded the following 

 volumes of oxygen, carbonic anhydride, and nitrogen after 

 being reduced to 0° C. and 760 mm. : — 



(c) Blood of Palinurus vulgavis. 



A hundred volumes of the blood of this animal gave the 

 following results : — 



