Fig. 4From: Hydroids (Cnidaria, Hydrozoa): A Neglected Component of Animal ForestsSome large cold-affinity hydrozoans . (a–f). Hydrozoans from British Isles, photo curtesy of Dr. Bernard Pictet http://www.habitas.org.uk/marinelife/. (a) Nemertesia antennina. (b) Nemertesia ramosa. (c) Polyplumaria flabellata. (d) Amphibestia operculata. (e) Hydrallmania falcata. (f) Halecium muricatum. (g) Lytocarpia myriophyllum from the Western Mediterranean. (h) The deep stylasterid Errina aspera from the Strait of MessinaBack to chapter page