Under the microscope, sea water reveals the larval stages of little-known marine creatures called phoronids (horseshoe worms), but finding their parents is another story. Although such fanciful larvae ...
PROF. MORTENSEN'S “Studies of the Larval Forms of Echinoderms”, reviewed in Nature for Dec. 8, 1921, is well known. He has now issued two sets of additional notes, * one resulting from a visit to ...