The range in time of the Ostracoda is so extended that, in G.
They may, however, be natatory as in many Ostracoda and Copepoda, or prehensile, as in some Copepoda.
Brady and Norman, in their Monograph of the Ostracoda of the North Atlantic and North-Western Europe (1889), give a bibliography of 125 titles, and in the second part (1896) they give 55 more.
The Ostracoda have the body enclosed in a bivalve shell-covering, and normally unsegmented.
In certain Copepoda and Ostracoda glands of the same type produce a phosphorescent substance, and others, in certain Amphipoda and Branchiura, are believed to have a poisonous function.
The Ostracoda might have been derived from the same stock were it not that they retain the mandibular palp which all the Phyllopods have lost.
In the Ostracoda and Copepoda the phosphorescence, as already mentioned, is due to glands which produce a luminous secretion, and this is the case also in certain members of the Schizopoda and Decapoda.
This zoological term, as now restricted, includes the Branchiopoda, Ostracoda and Copepoda.
They do not refer to Latreille, 1802, with whom the term Ostracoda originates.
The Phyllopoda, Ostracoda and Cirripedia (Thyrostraca) are represented in Cambrian or Silurian rocks by forms which seem to have resembled closely those now existing, so that palaeontology can have little light to throw on the mode of origin of these groups.