औपनिवेशिक सिल्टरेट्स जिसमें पॉलीप चरण प्रमुख है

Noun:

जल-सर्प से मिलता-जुलता, पनिहा साँप की तरह, हाइड्राइड,

hydroid's Usage Examples:

The hydroid Dicoryne 'is re- ' markable for the possession of gonophores, which are ciliate and become detached and swim away by means of their cilia.

In some cases both free medusae and gonophores may be produced from the same hydroid colony.

The first step towards the formation of a mixed hydroid colony is undoubtedly a hastening of the sexual maturity of the medusaindividual.

Moreover, all the medusae budded from a given hydroid colony are either male or female, so that even the non-sexual polyp must be considered to have a latent sex.

- In the Hydromedusae the medusa-individual occurs, as already stated, in one of two conditions, either as an independent organism leading a true life c2 a2 in the open seas, or as a subordinate individuality in the hydroid c colony, from which it is never set free; it then becomes a mere reproductive appendage or gono- phore, losing suc FIG.

Such are the " guard-polyps " (machopolyps) of Plumularidae, which are often regarded as individuals of the nature of dactylozoids, but from a study of the mode of budding in this hydroid family Driesch concluded that the guard-polyps were not true polyp-individuals, although each is enclosed in a small protecting cup of the perisarc, known as a nematophore.

Besides the three types of individual above mentioned, there are other appendages of hydroid colonies, of which the individuality is doubtful.

In this way the hydroid colony becomes composed of two portions of different function, the nutritive " trophosome," composed of non-sexual polyps, and the reproductive " gonosome," composed of sexual medusaindividuals, which never exercise a nutritive function while attached to the colony.

2) is a British hydroid.

The hydroid colony shows many variations in form and architec- ture which depend simply upon differences in the methods in which polyps are budded.

hydroid's Meaning':

colonial coelenterates having the polyp phase dominant