The majority of this reel was shot on the 1925 Arcturus Galapagos expedition; there is also some material from the 1923 Noma Arcturus Galapagos expedition. Isabel Cooper painting underwater. Moorish idol and moray eel. Hunting a giant manta ray. Bringing manta ray on deck. Examining and sketching it. Frigate birds courting. Sea lions swimming. Volcanic eruptions on Albemarle Island. Flowing of lava into ocean. Steam clouds rising and clouds formed from it overhead. Dr. Beebe and another man walking on the hot lava beds.