Gross morphology of the alimentary canal in 10 teleostean species.

The gross morphology of 10 teleostean alimentary canals was compared. Each short, tubular esophagus was connected either to a stomach or, in the agastric species, to a proximal intestinal swelling. 3 stomach types were differentiated according to their shapes, which appeared to be correlated somewhat with diet. Intestines showed variations in amount of coiling and in numbers of pyloric ceca. Ratios of gut lengths to body lengths (RGL, relative gut length) were calculated and the results of previous studies were confirmed in that the RGL of a planktivore was small, while that of an organic detritus feeder was large, and that of a carnivore fell in between.