Sperm whale . Myoglobin, which stores oxygen in muscle tissue, is much more abundant than in terrestrial animals. The blood has a high density of red blood cells, which contain oxygen-carrying haemoglobin. The oxygenated blood can be directed towards only the brain and other essential organs when oxygen levels deplete. The spermaceti organ may also play a role by adjusting buoyancy (see below). The arterial retia mirabilia are extraordinarily well-developed. The complex arterial retia mirabilia of the sperm whale are more extensive and larger than those of any other cetacean. Atop the whale's skull is positioned a large complex of organs filled
Cryptid whale female individual on Orkney, saying its dorsal fins was similar to a "mizzen mast", and the whale, based on Sibbald’s account, was described as "P. tursio". However, naturalist Georges Cuvier disregarded Sibbald’s claim as a bad description of the carcass, as well as dismissing the name "P. tursio". Another alleged sighting was off the Annapolis Basin, Nova Scotia, Canada on September 27, 1946, where the creature was apparently trapped there for 2 days. Its length was estimated to be between . The Alula whale, or the Alula Killer, or "Orcinus mörzer-bruynsus", was discussed and illustrated for the first time, but