▁reprodu ction . ▁In ▁common ▁with ▁other ▁b ry oz o ans , ▁Elect ra ▁pil osa ▁filter ▁fe eds ▁with ▁the ▁aid ▁of ▁a ▁crown ▁of ▁tent acles ▁known ▁as ▁a ▁l oph oph ore ▁with ▁which ▁it ▁sie ves ▁particles ▁from ▁the ▁water . ▁It ▁probably ▁fe eds ▁on ▁such ▁things ▁as ▁flag ell ates , ▁ph y top l ank ton , ▁b acter ia , ▁small ▁pieces ▁of ▁alg al ▁de br is ▁and ▁alg al ▁sp ores . ▁The ▁sp ines ▁on ▁the ▁ex os ke leton , ▁especially ▁the ▁long ▁one , ▁offer ▁protection ▁to ▁the ▁zo oid ▁when ▁it ▁is ▁feed ing ▁and ▁may ▁grow ▁longer ▁in ▁colon ies ▁facing ▁competition ▁from ▁other ▁b ry oz o ans . ▁The ▁growth ▁rate ▁of ▁the ▁zo oid s ▁var ies ▁with ▁the ▁water ▁flow , ▁the ▁temperature , ▁the ▁food ▁supply ▁and ▁the ▁competition ▁from ▁other ▁b ry oz o an ▁colon ies . ▁ ▁The ▁col ony ▁is ▁herm aph rod ite ▁but ▁individual ▁zo oid s ▁are ▁either ▁male ▁or ▁female . ▁In ▁Britain , ▁bre eding ▁takes ▁place ▁in ▁August ▁and ▁September . ▁The ▁males ▁liber ate ▁s perm ▁into ▁the ▁water ▁and ▁the ▁females ▁may ▁act ively ▁collect ▁this . ▁F ert il isation ▁takes ▁place ▁in ▁the ▁co el omic ▁cav ity ▁of ▁the ▁female ▁into ▁which ▁up ▁to ▁thirty ▁o ocy tes ▁are ▁released . ▁The ▁fert il ised ▁emb ry os ▁are ▁liber ated ▁into ▁the ▁sea ▁where ▁they ▁have