Plate XVII. 



Fig. 56. Obelia multidentata. 



A. Natural size. 



B. Portion of stern showing mode of branching and hydrotheca?. 



Fig. 57. Obelia plicata. 



A. Natural size. 



B. Portion of stem showing mode of branching and hydrothecse. 



FlG. 58. Obelia surcidaris. 



A. Natural size. 



B. Portion <>l colon} showing mode of branching, hydrothecae and gono- 



phore. 



Fig. 59. Calycella syringa. 



A. Natural size. 



B. Hydrothecse and gonophore (small type). 



C. Hydrothecae (large type). 



D. Hydrotheca with long pedicel. 



E. Gonophore (large type). 



Fig. 60. Campanulina forskalea. 



A. Natural size. 



B. Hydrothecae and hydranths. 



C. Branched colony. 



D. E. Hydrotheca?. 



Fig. 61. Campanulina rugosa. 



A. Natural size. 



B. Portion of stem showing hydrothecse. 



C. Gonophore. 



