The ratio of planocera reticulata , pheretima tschiliensis and nereis pelagica was 19 . 00 % , 20 . 13 % and 12 . 82 % . the conclusion of this study is the animal with strong motor ability and developed sense organ has little neuron body and more neuropil in ganglion 甲壳纲动物神经元胞体占神经节的比例最小(虾蛄和平背蜞神经元胞体所占神经节的比例分别为11 . 43和15 . 53 ) 。
