The Osteology and Relationships of the Echelid Eel, Kau.picbtbys diodonius'

INTRODUCTION THE MAIN FUNCTIONS of the present paper are to demonstrate that two very different families of eels have hitherto been included under the "Echelidae" and to allocate these families to their proper positions in the order Anguilliformes (or Apodes ). In order to establish these points, the osteology of Kaupichthys diodontus Schultz is dealt with in some detail. On September 7, 1949, an unripe female of this species, 155 mm . long , was taken by Strasburg, Welsh, and the author in a poison ; station in shallow water off the aquarium at Waikiki, Oahu, Territory of Hawaii. The species (and genus) was originally described by Schultz ( 1943: 50, pI. 6 and textfig. 5i ) from Tau and Rose Islands in the Samoan group. It is hitherto unrecorded from Hawaii. The specimen at hand differs from Schultz's description (and from a Bikini specimen dealt with below ) as follows : the teeth are blunter than indicated in his diagnosis and figure (5i); the two rows of vomerine teeth are not so widely separated, nor do they extend farther -posteriorly than the maxillary rows; and finally, the 'maxillary teeth are quite distinctly set apart from the premaxillary and vomerine groups. Whether the Hawaiian form merits specific or subspecific distinction, or whether the above-mentioned differences are merely individual or size variations, I do not have sufficient material to decide.