The type of insulin found in venom glands seems to match the prey of a given cone snail. (sciencedaily.com)
If the bombardier could evolve so complex a defense, it's not much of a stretch to imagine a dragon with venom glands filled with a gas that could ignite when released with just a bit of friction. (discovermagazine.com)
However, magnetic resonance imaging of a preserved Komodo head by the Fry team from the Museum of Natural History at Humboldt University in Berlin revealed an alternative explanation: huge venom glands opening to ducts at the front of the jaw. (newscientist.com)