Holocanthe à Demi-Cercles
The Holocanthe à demi-cercles is known in English as a semicircle angelfish. What’s interesting about this particular illustration is that it actually depicts a juvenile semicircle angelfish. Only the juveniles are blue-black in color, marked with narrow white stripes that curve from straight to semi-circular as they approach the base of the tail. Adults are instead a pale brownish-green, outlined in a bright blue. Fully-grown, the angelfish can grow to a length of fourteen inches, but it displays the juvenile markings until it is around 3 to 6 inches long. The semicircle angelfish lives in the Indo-Pacific region, in a range that extends from east Africa to Fiji and Japan as well as the east coast of Australia. However, in the last twenty years, it has been spotted as far away as Oahu, Hawaii and Florida.
This illustration is found in Histoire naturelle des poissons, a multi-volume collection compiled by Georges Cuvier and Achille Valenciennes. Cuvier was a major figure in the natural sciences, establishing the fields of comparative anatomy and paleontology by incorporating both living species and fossils into the existing taxonomy system. His work also revealed extinction to be fact, when previously it had been considered merely controversial speculation. Cuvier is best known for his book Le Règne Animal, or The Animal Kingdom, published in 1817. However, his researches on fish had begun as early as 1801. With the help of Achilles Valenciennes, who carried on the project after Cuvier’s death in 1832, he published the twenty-two volumes of Histoire naturelle des poissons between 1828 and 1849. The books contained descriptions of nearly 5,000 species of fish.
