These egg-cases belong to different members of the Ray family. I saw
one last winter, in which the inmate was fully developed. Should some
old seaman hear me, he might say that I am telling a "fish-story" in
good earnest. He might inform you furthermore, that the object in
question is "but a pod of sea-weed, and that he has seen hundreds of
them in the Gulf Stream." I cannot help it, neither do I question his
veracity. Notwithstanding, these two eyes of mine, in sound condition,
awake, and in broad day, did see the supposed pericarp, with one side
taken off, and did behold, lying within, as veritable a Raia as ever
was caught upon the New-England coast. Moreover, its countenance was
no more classical, in its minuteness, than that of its most ancient
ancestor in its hugeness.

Observe those bubbles trembling upon the edge of the wave. One is left
by the receding tide, and a nearer view shows it to be a jelly-like
globe, clearer than the crystal of Merlin. Dropped softly into a
vessel of water, at first it lies quiescent and almost invisible upon
the bottom. A moment after, it rises in quick undulations, flashing
prismatic tints with every motion. Again it rests, and we see that it
is banded by eight meridians, composed of square, overlapping plates.
It swims, and the plates become paddles, propelling the frail craft,--
prisms, dividing the sunbeams into rainbow hues. Suddenly two lines of
gossamer are dropped from unseen openings in its sides, and trailed
behind it as it goes. Twisting, lengthening, shortening, they are
drawn back and re-coiled within, and

"The ethereal substance closed,
Not long divisible."