This set of photomicrographs by Dr. Anita Brinckmann Voss shows a colony growing on a frond of Aglaophenia sp.
see this link for other hydroids: https://www.racerocks.ca/tag/hydroid/
Species recognized by World Register of Marine Species (WoRMS):
Biota
Animalia
Cnidaria
Hydrozoa
Hydroidolina
Anthoathecata
Filifera
Hydractiniidae L. Aggasiz, 1862
Hydractinia Van Beneden, 1841
Hydractinia laevispina Fraser, 1922
Return to the Race Rocks taxonomy and photo gallery