Noun
The Acalephae; one of the classes of coelenterates, including the Hydroidea, Discophora, and Siphonophora.
of Hydrozoon
Source: Webster's dictionaryA comprehensive morphological cladistic analysis by Schuchert (1993) supports the basal position of Anthozoa with the Scyphozoa and Cubozoa being more closely related to each other than to Hydrozoa. Source: Internet
Box jellyfish may be related more closely to scyphozoan jellyfish than either are to the Hydrozoa. Source: Internet
That research also proposes coronate Scyphozoa and Cubozoa as a sister clade to Hydrozoa and discomedusan Scyphozoa, which are themselves sister groups. Source: Internet
When at last he got a grant from the Royal Society for the printing of plates, Huxley was able to summarise this work in The Oceanic Hydrozoa, published by the Ray Society in 1859. Source: Internet