original description
(of Hydractinia allmanii Bonnevie, 1898) Bonnevie, K. (1898). Zur Systematik der Hydroiden. <em>Zeitschrift für Wissenschaftliche Zoologie.</em> 63: 465-495, plates 25-27., available online at https://www.biodiversitylibrary.org/page/43167443
page(s): 485, pl. 26 figs 36-37 [details]
original description
(of Hydractinia ornata Bonnevie, 1899) Bonnevie, K. (1898). Zur Systematik der Hydroiden. <em>Zeitschrift für Wissenschaftliche Zoologie.</em> 63: 465-495, plates 25-27., available online at https://www.biodiversitylibrary.org/page/43167443
page(s): 485, pl. 26 fig. 41. [details]
redescription
Rees, W.J. (1956). On three northern species of Hydractinia. Bull. Br. Mus. Nat. Hist., Zool. 3 8: 351-362. <em>Bulletin of the British Museum (Natural History).</em> 3: 351-362., available online at https://www.biodiversitylibrary.org/page/2243899
page(s): 352, pl. 11 figs 1-7; note: as Hydractinia allmanii [details]
redescription
Schuchert, P. (2008). The European athecate hydroids and their medusae (Hydrozoa, Cnidaria): Filifera part 3. <em>Revue suisse de Zoologie.</em> 115: 221-302.
page(s): 241, fig. 7; note: as Hydractinia allmanii [details] 
new combination reference
Miglietta, M. P., & Cunningham, C. W. 2012. Evolution of life cycle, colony morphology, and host specificity in the family Hydractiniidae (Hydrozoa, Cnidaria). Evolution 66: 3876-901., available online at https://doi.org/10.1111/j.1558-5646.2012.01717.x
page(s): 5; note: Caveat: examined material was growing on hermit crabs and not gastropods, thus identification could be erroneous [details] Available for editors 
biology source
Rees, W.J. (1956). On three northern species of Hydractinia. Bull. Br. Mus. Nat. Hist., Zool. 3 8: 351-362. <em>Bulletin of the British Museum (Natural History).</em> 3: 351-362., available online at https://www.biodiversitylibrary.org/page/2243899
page(s): 355; note: Always on living gastropod Colus sp. (Rees, 1956c: 355, as Sipho curtus (Jeffreys)) [details]
From editor or global species database
Biology Always on shells of the gastropod Colus sp. (Rees, 1956c: 355, as Sipho curtus (Jeffreys)) [details]