Bush, Katharine Jeannette. (1907). Notes on the relation of the two genera of tubicolous annelids, Vermilia Lamarck, 1818 and Pomatoceros Philippi, 1844. The American Journal of Science. Series 4. 23(133): 52-58.
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In 1844 Philippi described a species from the Mediterranean, figuring its operculum (P) under the name of
Pomatoceros tricuspis, creating for it the then new genus Pomatoceros, at the same time calling attention to its possible identity with Serpula triquetroides Delle Chiaje '28, which identity was established by Claparède '69 (p. 182). Philippi also pointed out its resemblance to Vermilia triquetra Lamarck '18, but on a later page applied this latter name to a form having a different operculum cap, which he also figured (F).