TOUCH. 383 



those instruments which are more particularly- 

 intended as organs of touch, should possess this 

 property. 



It will not be necessary to enter into a minute 

 description of these organs, because they have, 

 for the most part, been already noticed as in- 

 struments of prehension ; for the sense of touch 

 is in general exercised more particularly by the 

 same parts which perform this latter function. 

 Thus the ten taenia of the various tribes of 

 Polypi, of Actiniae, and of Annelida, are organs 

 both of prehension and of touch. The tubular 

 feet of the Asterias and Echinus are, in like 

 manner, subservient both to the sense of touch, 

 and to the faculty of progressive motion. The 

 feet of Insects and of Crustacea are well cal- 

 culated, indeed, by their jointed structure, for 

 being applied to the surfaces, and to different 

 sides of bodies ; but they are scarcely ever em- 

 ployed in this capacity ; being superseded by the 

 palpi, which are situated near the mouth. When 

 insects are walking, the palpi are incessantly 

 applied to the surface on which they advance, 

 as if these organs were especially employed to 

 feel their way. There can be little doubt, how- 

 ever, that, in most insects, the principal organs 

 of touch are the A?itennce, also denominated, from 

 their supposed office, the feelers * 



Some idea of the great variety in the forms of 



* The German name for them, fiihlhorner, or the feeling 

 horns, is founded on the same notion. 



