lateral view of the miracidium of Megalodiscus temperatus, drawn by
Thomas P. Buckelew, Ph. D. The large cluster of cells near the upper end is the
ganglion which acts as a central nervous system and contains adrenergic-like
vesicles. The large secretory sac can be seen extending almost the length
of the larva. The coiled tubules are the flame cells. 1000x.