hydroids

Hydroidshydroids Hydroids, or sea-firs, are plant-like animals. They resemble fir-like plants, but are actually the simplest of stinging-celled animals. The cells of these animals contain capsules (called cnidae), and these capsules contain a long hollow, coiled thread which uncoils and shoots out under water pressure when the cell is triggered by touch or water pressure. These threads, whose precise characteristics vary according to species, capture the prey., or sea-firshydroids Hydroids, or sea-firs, are plant-like animals. They resemble fir-like plants, but are actually the simplest of stinging-celled animals. The cells of these animals contain capsules (called cnidae), and these capsules contain a long hollow, coiled thread which uncoils and shoots out under water pressure when the cell is triggered by touch or water pressure. These threads, whose precise characteristics vary according to species, capture the prey., are plant-like animals. They resemble fir-like plants, but are actually the simplest of stinging-celled animals. The cells of these animals contain capsules (called cnidae), and these capsules contain a long hollow, coiled thread which uncoils and shoots out under water pressure when the cell is triggered by touch or water pressure. These threads, whose precise characteristics vary according to species, capture the prey.