ABSTRACT
Antedon bifida, a sublittoral crinoid from energetic and food-rich waters around the western coasts of the British isles, has a less marked seasonal periodicity than other echinoderms that have been studied from the same waters. While there is a clear increase in the production of mature oocytes and a higher mean size of oocytes in May/June (early summer), large oocytes are present almost throughout the year. Similarly in males there are few periods in the cycle in which the testes do not contain mature sperm. Shed embryos adhering to the external pinnular wall have, however, been seen only in May to July, and spawning has been observed only in July. The reproductive strategy shown by this species resembles that of certain temperate Pacific and some tropical species of comatulids.
