hydranth

/hahy-druhnth/US // ˈhaɪ drənθ //UK // (ˈhaɪdrænθ) //

水力发电,水力,水力资源,水力发电站

Definitions

n.名词 noun

1
Zoology.
- : the terminal part of a hydroid polyp that bears the mouth and tentacles and contains the stomach region.

As a general rule polyp-buds are produced from the hydrorhiza and hydrocaulus, while medusa-buds are formed on the hydranth.
Hydranth more shortened, daisy-like in form, with two whorls of tentacles, oral and aboral.
Speaking generally, three principal types of hydranth can be distinguished, each with subordinate varieties of form.
Hydranth with tentacles reduced below four; type of Lar (fig. 11), Monobrachium, &c.
In both cases the hydranth is extremely reduced and has no tentacles, and the polyp forms a colony by budding from the base.