A hollow cell in the excretory system of certain invertebrates, including flatworms and rotifers, containing a tuft of rapidly beating cilia that serve to propel waste products into excretory tubules.焰细胞：某种无脊椎动物（包括扁虫和轮虫）在排泄系统中的空细胞，具有用来把废物推向排泄管的一簇能迅速摆动的纤毛