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Eight species of tunas and bonitos are known to occur in the Gulf of Mexico, Caribbean Sea, and adjacent Atlantic waters. Seven of these have been utilized, at least on a small scale, in commercial packs of canned tuna. Gulf and Caribbean catches of some species have been processed for the first time as recently as 1955. The presence of tuna as a widely distributed resource available to longlines was demonstrated by the U. S. Fish and Wildlife Service exploratory fishing vessel Oregon in 1954 and 1955, supporting the views of a few earlier observers that the rare appearance of large numbers of tuna in Gulf and Caribbean offshore waters indicated the existence of a diverse but substantial sub-surface population. Effective exploitation of the resource and the development of a prosperous longline fishery probably depends on many factors, not limited to, but including the development of a stable market at locations convenient to fishermen and rapid extension of our knowledge of the areas and seasons ...

Two new species of the squalid shark genus Etmopterus are described from the Caribbean coast of Colombia. Both new species are very small and may represent the smallest known species of sharks. Males and females of the type series (180-212 mm TL) of Etmopterus carteri are sexually mature; Etmopterus perryi males become sexually mature at about 160-175 mm TL and gravid females are found at 190-200 mm TL. A key to the eight Carribbean species is included.

Two roots are described for the glossopharyngeal nerve in Silurus (Berkelbach 1915), in Parasilurus (Atoda 1936), in Wallago (Sinha, doctoral dissertation), and in Mystus (Mithel 1964), whereas there is only 1 such root in Bagarius. The lateral ramus of the vagus and the vagus nerve have separate origins from the brain in Parasilurus. In Wallago and in Mystus, the vagus nerve originates from 2 roots, which unite and then separate into the lateral ramus of the vagus and the common stalk of the branchial and visceral

In recent sawfishes, Pristis (order Batoidei), rostral teeth that are lost are not replaced and those not severely damaged in use increase in size throughout life. Presumably similar conditions pertain to fossil sawfish genera having socket-like attachments for rostral teeth. In recent sawsharks, Pristiophorus and Pliotrema (order Selachii), rostral teeth are replaced if lost and do not increase in size after reaching a functional position. Similarities in tooth development and the process of replacement were observed in recent sawsharks (Selachii) and in the Cretaceous sawfish genus Sclerorhynchus (Batoidei). Also, the pattern of varying length of rostral teeth in adults of recent sawsharks (Selachii), which is explained by the appearance of both new and replacement teeth at intervals during growth, offers a possible explanation for the presence of rostral teeth of various lengths in the Cretaceous ganopristid sawfish Onchopristis numidus (Batoidei).