paper-clip plug, serves as a thermobarometer balancing 

 the reaction vessel while a drop of alkali absorbs the C0 2 

 evolved. By using a 2x hand lens to read the micrometer, 

 volume changes of as little as 0. 004 to 0. 007 mm 3 may be 

 detected. A second respirometer containing seawater, but 

 no organism, is run as a control. All equipment is mounted 

 in a constant -temperature bath controlled to at least ±0. 1°C. 

 Figure 6, obtained from Experiment 8, indicates the linear- 

 ity of rates of oxygen consumption determined by this 

 method. The rates shown in table 1 were corrected for 

 seawater controls (see Appendix A). 



70 



60 



50 



40 



30 



20 



10 





















•/ 



















•/ 

















s** 















UN 



:orreci 



WjS 















































































CORRECTED FOR CONTROL 







10 



20 



30 



40 50 ffl' 

 MINUTES 



70 



90 



100 



Figure 6. Rate of oxygen uptake by a siphonophore (Experiment 8). 

 Values are corrected for seawater controls. 



14 



