Brain as an organ of mind / by H. Charlton Bastian.

  • Bastian, H. Charlton.
Date:
1880
Catalogue details

Licence: Public Domain Mark

Credit: Brain as an organ of mind / by H. Charlton Bastian. Source: Wellcome Collection.

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    plexity, some of the tactile structures within or around the mouth may undergo a further specialization, by which they and their related nerve centres become fitted to dis- criminate between impressions of a slightly different nature. Such ‘ organs of taste ’ would become sensitive to the more refined kind of contact yielded by certain dissolved elements of the food, whose local action is perhaps attended by some slight chemical change in the tissues of the part. Impressions are thus produced whereby the ‘ sapidity ’ or flavour of bodies is appreciated; and such impressions gradually become associated with definite related movements, partly of internal and partly of external organs. Although this mode of impressibility doubtless exists in many of the lower forms of life, still no distinct organ of Taste, or specialized gustatory surface, is as yet actually known to occur among invertebrate animals, except in Insects and in such higher mollusca as Snails and Cuttle- fishes. Impressions of the two orders already referred to— more or less distinct from one another—are those by which alone multitudes of the lower forms of animal life, such as Polyps and various kinds of Worms, appear to hold converse with the outside world. Seeing, however, that tactile and gustatory impressions can only be made by actual contact of external bodies with the specialized parts of an organism, such impressions are not of a kind to excite movements in ‘ quest * of food; although they may lead to correlated motions of parts adjacent to those touched, as in the acts of prehension and swallowing. Sight.—Movements in actual quest of food may, how- ever, be excited in other animal organisms by impressions bringing them into relation with more or less distant bodies. The way is paved for this result when some