Fig. 1. — Bimeria annulata. Perisarc surrounding hydranth, the latter 

 having been removed by caustic, potash, x 30. 



Fig. 2. — Same species. Hydranth, showing continuation of perisarc upon 

 tentacles. x30. 



Fig. 3. — Same species. Gonophore, with original perisarcal investment 

 partially retracted. x 30. 



Fig. 4. — Bimeria franciscana. Portion of a main branch, x 



Fig. 5. — Bimeria robusta. Hydranth. x40. 



Fig. 6 — Same species. Young hydranth; perisarc extending over bases of 

 tentacles. x40. 



Fig. 7. — Same species. Semi-diagramatic view of a developing hydranth 

 from above, to show the order of appearance and arrangement 

 of the tentacles, x 40. 



Fig. 8. — Clava leptostyla. Heteromorphic regeneration of a piece of 

 stem; a set of tentacles at each end. 



Fig. 9. — Same stem, two days later. 



Fig. 10. — C. leptostyla. Regeneration of a hydranth; stage with four ten- 

 tacles. 



Fig. 11. — Same individual, twenty-four hours later; second quartette of 

 tentacles appearing. 



Fig. 12. — Same: third quartette appearing. 



