Biologists dealing with present marine and freshwater fishes are fortunate in having the required biological information directly available in most cases. Identification of the species, age, sex, size, weight, place, and environmental conditions are all easily obtained. Paleontologists and archaeologists have to estimate data on live fish by indirect methods, drawing their information from fossilized or preserved bones. Bones are the only anatomical parts that remain for a considerable time after the death of the fish. As such, they are witness of past existence and repositories of an enormous amount of biological and ecological information. The names applied to fish bones run into the hundreds. Many are synonyms, some are erroneous, some are misnomers, some are only known and used in a particular country, and finally, some have been found to be consistent with the principle of homology and therefore have been retained without change up to the present.