'Minute transparant early stage of a sea-cucumber. It swims in the open sea by means of girdles of microscopic cilia shown in the figure. After a period of free swimming and a remarkable metamorphosis, the animal settles down on the floor of the sea in relatively shallow water'.
'A common starfish, which has loft three arms and is regrowing them. The lowest arm is being regrown double'.
Found in the ebook 'The Outline Of Science' volume 1 of 4, by J. Arthur Thomson. See more here.