入鳃动脉主干上具有膨大的圆形隆起，可能起类似血泡的鳃心作用，尚与鳃部本身的物质交换有关；
On the afferent gill arterial trunk are the round protruding structures which may serve as a branchial heart of the blood blebs and may concern with the material exchange of the gill .
鳃心