Histology and sexual reproduction of the anemone<i>Nematostella vectensis</i>Stephenson 1935

Abstract

The histology of the anemone Nematostella vectensis Stephenson from Minas Basin, Nova Scotia was investigated using four straining techniques. These revealed the presence of at least four types of gland cells. With one exception, nematocysts averaged smaller than those measured by Hand (1957). Longitudinal retractor muscles and elastic fibres in the mesenteries sandwiched a narrow band of mesoglea, contradicting diagrams in Stephenson (1935) and Crowell (1946). Dioecious occurrence of gonads were found in 6 of 276 anemones examined and only in anemones collected during August and September. Development to planula stage has been observed.