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POPULAR SCIENCE MONTHLY
11. Adaptive Radiation in the Characinidæ. The central figure of Astyanax bimaclatus with notched teeth probably represents the more primitive condition. The lower left hand figure represents Anodus latior with no teeth and a very long alimentary canal, a mud eater. The lower right-hand figure represents the scissor-like jaw and teeth of Serrasatmo humeralis whose relatives have been repeatedly reported to have killed bathers before they could reach shore after being attacked. The upper figure represents Raphiodon vulpinus Spix which has reached the extreme in conical teeth, the large canines protruding above when the jaws are closed. The over 100 South American genera and 500 species of this family offer pretty complete series from the center to the extremes with many lateral branches.
