Ctenophora
an order of Actinozoa, consisting of marine animals which swim by means of ctenophores. The body, which is gelatinous and transparent, is generally more or less oval in form.
Most of the species have a pair of very extensible filiform tentacles. There are two tribes, eurystomata and stenostomata, the first containing the family beroidæ, and the second the families saccatæ, lobatæ, and tæniatæ. The ctenophora are found in all seas.