11. These include algae, polychaete worms, sea anemones, barnacles, bryozoans and hydroids . 12. It was found on hydroids in Panama. 13. It is known to feed on hydroids of the genus " Eudendrium ". 14. Most species are predators of hydroids . 15. In this work Nutting described 124 new species and beautifully illustrated his monograph on American hydroids . 16. The majority of hydroids are substrate and forms a bud which remains attached to its parent. 17. These marine hydroids live in the shelly tubes of serpulid tube worms, which are annelids. 18. It can be found on hydroids . 19. The existence of some floating hydroids on Georges Bank has been known for more than 80 years. 20. The hydroid grows rapidly and may starts to produce medusae when as little as seven weeks old.
