Presents the video “Spirit of Discovery” on Friday, April 19, at noon, in Redfield Auditorium, 45 Water St., Woods Hole. A quarter of a million “flying” Devil Rays shouldn’t be hard to find.  But Dr. Walter Munk and company are two days into their expedition, and with three science boats, an ultralight airplane, and radio reports coming in from every fisherman in Baja, they can’t still find a single ray.  Something’s wrong. Walter’s previous discoveries landed the D-Day troops at Normandy, decoded the dark side of the moon, revealed that ocean temperatures are rising, created surfcasting, and set off the first sound that was literally “heard round the world.”  Now, one of the most important Oceanographer finds himself venturing into the unfamiliar waters of marine biology. This expedition is different.  This time, it’s personal. Sponsored by the WHOI Visitor Center. Coffee, tea, and cookies served. Donations accepted.