National Geographic on blue whales:

The blue whale, Balaenoptera musculus, is the largest creature ever to live. Linnaeus derived the genus name from the Latin balaena, “whale,” and the Greek pteron, “fin” or “wing.” His species name, musculus, is the diminutive of the Latin mus, “mouse”—apparently a Linnaean joke. The “little mouse whale” can grow to 200 tons and 100 feet long. A single little mouse whale weighs as much as the entire National Football League. Just as an elephant might pick up a little mouse in its trunk, so the elephant, in its turn, might be taken up by a blue whale and carried along on the colossal tongue. Had Jonah been injected intravenously, instead of swallowed, he could have swum the arterial vessels of this whale, boosted along every ten seconds or so by the slow, godlike pulse.