Variations: Serre, Pristis, Vivella, Sawfish, Saw-fish, Flying Fish
The Serra (“saw”) or Saw-fish is a mainstay of bestiaries. Traditionally identified with the sawfish, it also includes features of the flying fish and comes with a ready moral message for the benefit of faithful readers.
Pliny mentions a fish named Pristis which is two hundred cubits (over 90 meters) long, is viviparous, and seemingly covered with hair. Pristis was also a common name given by Romans to ships. Isidore of Seville gives us the ur-description of the serra as a fish with a serrated (serratus) crest which cuts through boats as it swims under them.
Later additions expanded on this account. The serra is a huge seagoing fish or monster with gigantic fins. When it sees a ship, it spreads its fins, catching the wind, and chases after the vessel in an attempt to outspeed it. After two hundred yards the serra gets bored, folds its wings, and sinks back into the ocean. The ship represents the Righteous, who press on in the face of adversity, while the serra represents fickle and lazy people who start out trying to be Christians but discourage easily.
Why the serra chases after the ship is uncertain. The moral suggests jealousy, but the propensity of the serra to slice up ships with its saw-crest implies a more malevolent motive. Other accounts describe it as more bloodthirsty, sinking ships to feast on sailors, while some (perhaps confused with dolphins?) are said to take pity on sinking ships and lift them out of the waves.
The serra does not fly, instead using its massive fins move like a sailboat, but medieval artists commonly show it flying above ships anyway. Eventually the serra’s iconography was muddled with the dragon’s, and it became another dog-like or reptilian winged monster.
The position of the saw has also been a subject of contention. Isidore of Seville’s crest (crista) was interpreted in ways ranging from a rooster’s comb to a saw-edged dorsal fin. None of them locate the saw on the end of the nose.
Buel regards the sawfish as an innocent and inoffensive creature. The occasional attacks on boats are attributed to parasitic copepods, whose burrowing into the sawfish’s flesh drives the creature into delirious agony and causes it to lash out at anything nearby.
References
Aldrovandi, U. (1613) De Piscibus, Libri V. Bononiae.
Buel, J. W. (1887) Sea and Land. Historical Publishing Company, Philadelphia.
Cuba, J. (1539) Le iardin de santé. Philippe le Noir, Paris.
Druce, G. C. (1919) On the Legend of the Serra or Saw-fish. Proceedings of the Society of Antiquaries, Second Series, v. 31.
Hippeau, C. (1852) Le Bestiaire Divin de Guillaume, Clerc de Normandie. A. Hardel, Caen.
Isidore of Seville, trans. Barney, S. A.; Lewis, W. J.; Beach, J. A.; and Berghof, O. (2006) The Etymologies of Isidore of Seville. Cambridge University Press, Cambridge.
Pliny; Bostock, J. and Riley, H. T. trans. (1900) The Natural History of Pliny, v. II. George Bell and Sons, London.
White, T. H. (1984) The Book of Beasts. Dover Publications, New York.