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Keywords from Image Description:
a. Skull of the Beaver Castor fiber b. Vertical view of the teeth. a. Skull of the American Porcupine Hystrix hudsonius b. Upper jaw teeth of the same c. Lower jaw of the same. a. NYPL b. en Skull of the Beaver Castor fiber Vertical view of the teeth Skull of the American Porcupine Hystrix hudsonius Upper jaw teeth of the same Lower