PLATE VIII. 



[Proc. Wash. Acad. Sci., Vol. Ill, PI. XIX.] 



FIG. I. Campanularia regia Nutting. Single hydrotheca, showing hydranth 

 (much less enlarged than the other figures). 



2. Another hydrotheca, showing reduplication of margin. 



3. Hydrotheca of C. speciosa Clark (drawn to the same scale as fig. i, to 

 show comparative size). 



4. Obelia borealis Nutting. Part of colony, showing hydrothecse and 

 gonangium (enlarged). 



5 and 6. Gonangia (greatly enlarged). 

 [202] (220) 



