The Perciform Caudal Skeleton

primarily one of progressive simplification from an original complex of rather numerous independent bones (e.g., in Elops, Hollister, 1936:261, fig. 14). This progressive simplification has occurred independently in a large number of lineages both within and below the perciform level of structural organization. The material on which the present paper is based falls into two categories. The first consists of a series of alizarian-stained (but not cleared) specimens dissected especially in connection with the present work. The specimens in this category are: Serranidae, Cephalopholis urodelus, 73 mm in standard length; Apogonidae, Apogon snyderi, 95 mm; Mullidae, Mulloidichthys samoensis, 87 mm; Carangidae, Caranx melampygus, 94 mm; Labridae, Cheilio inermis, 85 mm; Embiotocidae, Damalichthys vacca, 91 mm; Polynemidae, Polydactylus sexfilis, 104 mm; Sphyraenidae, Sphyraena barracuda, 110 mm; Atherinidae, Pranesus insularum, 75 mm; and Monacanthidae, Pervagor spilosoma, 84 mm. The second category, which includes all other fishes mentioned in the paper, is based on specimens in the skeleton collection of the University of Hawaii. At the present time it would often be impossible to determine the length of the specimens in this category; all that can be said is that skeletons were al-