Views in the 1930s
As background for later developments, this chapter will describe some of the reigning views from the latter 1930s concerning cells, membranes, proteins, and metabolic systems. A brief account of some of the methods then available is also included.
Some Pliocene Fishes from Kansas, Oklahoma, and Nebraska
served in dead specimens are the series of bright blue streaks on the scaleless portions of the dorsal and dorsolateral surfaces, the white anterior edge of the first dorsal fin, the silvery tongue, and the dark vertical bands on the dorsolateral surfaces, the latter seen only in feeding skipjack. The two size groups schooled together. School disruption occurred only during feeding. The fish swam with their mouths constantly agape. They were never observed to stop swimming. No rheotaxis was demonstrated.
Ictalurus lambda, a New Catfish, Based on a Pectoral Spine from the Lower Pliocene of Kansas'
family Ameiuridae, of the siluroid (nematognathous) division of the Ostariophysi, not only because it agrees most satisfactorily with the pectoral spines at hand of Recent species of that family, but also because of varied circumstantial evidence. This family comprises the North American freshwater catfishes and is thought to date, at least, from the Eocene. It is a plausible inference that this group lived in the streams that laid down the Ogallala formation in a climate that appears to have been mild-temperate.