HYDROMEDUSAE, a group of marine animals, recognized as belonging to the Hydrozoa by the following characters.
Sub-class Hydromedusae (Hydrozoa Craspedota).
Cylindrical or tapering from The numbers in square brackets  refer to the bibliography at the end of this article; but when the number is preceded by the word Hydrozoa, it refers to the bibliography at the end of the articl Hydrozoa.
C. Chun, [[Hydrozoa [I]]], pp. 3 1 4, 315).
- The general structure and characteristics of the medusa are described elsewhere (see articles Hydrozoa and Medusa), and it is only necessary here to deal with the peculiarities of the Hydromedusa.
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