reproductive system

4 Turbellarians are monoecious with the reproductive systems adapted for internal fertilization. And the monogenetic flukes (class Monogenea) are mostly ectoparasites of fishes.

涡虫是雌雄，生殖系统适于内受精。单起源吸虫（单殖纲）大多是鱼外生虫。

Trochus pyramis Born is of gonophores.The male reproductive system is mainly composed of the spermaries and spermaductus, instead of mating and others glands.

摘要塔形马蹄螺为雌雄异，其雄性生殖系统主要由精精管组成，没有交接器，也没有其他附属腺。