FUNCTIONS OF SWIMBLADDER OF FISHES. 



8 9 



explains how such fishes are able to go into regions of low oxygen 

 content and live for several hours. The question can be 

 answered tentatively by certain theoretical considerations. A 

 normal perch of average size has a swimbladder capacity of 



TABLE IV. 



ANALYSES OF THE GASES OF THE SWIMBLADDERS OF PERCH SUBJECTED TO WATERS 



OF Low OXYGEN CONTENT, IN A WIRE CAGE IN LAKE MENDOTA. 



SEPTEMBER 7 TO 15, 1921. 



