The correct plural of appendix depends on the circumstances. When referring to the text at the end of a book or article, the plural is appendices. In the sense of the organ, appendixes is the only plural. Compare vacuum, which can pluralize to vacua or vacuums depending on the meaning.
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Almost every sentence in it is enigmatic. As now published, there are always subjoined to it certain appendixes, which are ascribed to Confucius himself.
The two appendixes attached to the upper lobe or lobus pyramidalis, and known in modern nomenclature as processus pyramidalis and processus papillaris, were described respectively as the "finger" of the liver and as the "offshoot."
The former of these two appendixes plays an especially important part in hepatoscopy, and, according to its shape and peculiarities, furnishes a good or bad omen.