PLATE 5 



Tubulipora flabellaris, iJortiou of characteristic zoarium. 



Boioerhankia gracilis, portion of zoarium, the var. caiuhitd Hincks. 



Alcyonidium parasiticn7n, showing mode of growth. 



The same, young zooecia at edge of zoarium. 



Alcyonidium polyoum, young, uncrowded zooecia at edge of zoarium. 



The same, older part of colony. 



The same, crowded condition of growth. 



FhistrcIIn hispidd, habit of growth and partly covered by BowerhanJcia 



364 



