These crustaceans provide a valuable food source for some fish.这些甲壳纲动物是某些鱼类重要的食物来源.When the tide ebbs it's a rock pool inhabited by crustaceans.退潮时，它便成为甲壳动物居住的岩石区潮水潭。Sir. J . Lubbock has recently remarked , that sev...
small freshwater crustaceans with a shield-shaped carapace长有盾牌状甲壳的小型淡水甲壳动物Sir. J . Lubbock has recently remarked , that several minute crustaceans offer excellent illustration of this law.卢布克爵士最近指出, 小型甲壳类中有几种较好的例子,可作为这一法...