1915 



Zeller and Neikirkj on Nereocystis 



27 



The gas from the pneumatocysts was collected in jars by water 

 displacement. The inverted jars were carefully sealed under water to 

 prevent any mixture of air with the gas. The collections were made at 

 3:00 to 4:00 o'clock p. ni. and 3:00 to 4:00 o'clock a. m. on different 

 days. In this way the effects of photosynthesis and nocturnal respiration 

 on the variation of the tM'o gases in question could be determined. Tables 

 I and II contain the results of the analyses for carbon dioxid and oxygen, 

 respectively. 



Table I. Showing the analyses for carbon dioxid. 



Average variation of CO, from day to night 2.21%. 



