The Roman History · Amm. 22.15.16

And as he is armed with claws, if he had only thumbs his enormous strength would suffice to upset large vessels, for he is sometimes ten cubits long. At night he sleeps under water; in the day he feeds in the fields, trusting to the stoutness of his skin, which is so thick that missiles from military engines will scarcely pierce the mail of his back.

Ammianus Marcellinus · translated by C. D. Yonge · 1911 reprint
C. D. Yonge translation (preface dated February 1862); G. Bell and Sons, 1911; Project Gutenberg #28587
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