ALIMENTARY Duct or Canal, is a name given by Dr Tyson and some others to that part of the body thro' which the food passes, from its reception into the mouth to its exit at the anus; including the gullet, stomach, and intestines. See ANATOMY.
This duct has been said to be the true characteristic
of an animal, or (in the jargon of the schools) in proprio quarto modo; there being no animal without it, and whatever has it being properly enough ranged under the class of animals. Plants receive their nourishment by the numerous fibres of their roots, but have no common receptacle for digesting the food received, or for carrying off the reclements. But in all, even the lowest degree of animal life, we may observe a stomach and intestines, even where we cannot perceive the least formation of any organ of the senses, unless that common one of feeling as in oysters. Phil. Trans. No 269, p. 776, seq.
Dr Wallis brings an argument from the structure of the alimentary tube in man, to prove that he is not naturally carnivorous; to which Dr Tyson makes some objections. V. Phil. Trans. No 269, p. 777.