IMMEDIATE FUNCTION OF TASTE. 155 



longata, and separating their roots from those of the pneumogastric, 

 contractions always ensued in the stylo-pharyngeus muscle. From all 

 the facts adduced by recent observers, Mr. Paget 1 thinks it probable, 

 First. That the glosso-pharyngeal is chiefly the nerve of taste, and, in 

 a less degree, a nerve of common sensation ; and Secondly. That, 

 according to the experiments of MM. MUller and Hein, it is the motor 

 nerve of the stylo-pharyngeus, and probably also of the palato-glossus. 



Lastly, M. de Blainville supposes, that the sense of taste is, per- 

 haps, neither sufficiently special nor sufficiently limited in extent to 

 have a separate nervous system; and therefore that all the nerves of 

 the tongue are equally inservient to the sense, as the different nerves 

 of the skin, which proceed from numerous pairs, are equally inservient 

 to touch or tact. 2 



Such is the existing state of uncertainty regarding this interesting 

 point of physiology: the view of Panizza appears, however, to the 

 author, to be most in accordance with analogy; and in all respects most 

 worthy of adoption. From the experiments and observations of Bellin- 

 geri, Montault, Diday, C. Bernard, and Verga, 3 it would appear, that 

 the filaments of the chorda tympani, which are united and confounded 

 with those of the lingual branch of the fifth pair, are in an inexplicable 

 manner connected with gustation. When the facial nerve has been 

 paralyzed, or divided above the origin of the tympanic branch, the 

 sense of taste has been impaired. The functions of the chorda tym- 

 pani are by no means determined; some esteeming it as a sensory, 

 others as a motor nerve; whilst others, again, believe it to possess both 

 sensory and motor properties. 



The immediate function of taste, as has been remarked, is to give 

 the sensation of savours. This function, like touch, is instinctive; 

 requires no education ; cannot be supplied by any of the other senses, 

 and is accomplished as soon as the tongue has acquired the necessary 

 degree of development. To this it may be replied, that the very young 

 infant is not readily affected by savours. In all cases, however, cer- 

 tain sapid bodies excite their usual impression; and, in the course of a 

 few months, when the organ becomes developed, the sense acquires a 

 high, and often inconvenient, degree of acuteness. 



The mediate or auxiliary offices of gustation are few, and limited in 

 extent. It does not afford much instruction to the mind. The chemist 

 and mineralogist occasionally gain information through it; but it is 

 never considered to merit the rank of an intellectual sense : on the con- 

 trary, it is classed with olfaction as a corporeal sense. 



To appreciate a savour accurately, the sapid substance must remain 

 for a time in the mouth: when rapidly swallowed, the impression is 

 feeble, and almost null. Of this fact we take advantage when com- 

 pelled to swallow nauseous substances ; whilst we retain a savoury arti- 

 cle long in the mouth, in order that we may extract its sweets. How 

 different, too, is the consent of the auxiliary organs under these two 

 circumstances! Whilst a luscious body augments the secretion of the 



1 Brit, and For. Med. Rev., April, 1845, p. 580. 



3 Adelon, op. cit., i. 309. s Cited by M. Longet, op. cit, p. 365, Paris, 1850. 



