OF TOUCH. 153 



231. The skin, whose structure we formerly examined, 

 is the general organ of* touch.* The immediate seat is 

 the papillae of the corium, of various forms in diffe- 

 rent parts, commonly resembling warts,f in some places 

 fungous, | in others filamentous. § The extremities of 

 all the cutaneous nerves terminate in these under the 

 form of pulpy penicilli. 



232. The hdnds are the principal seat of touch pro- 

 perly so called and regarded as the sense which ex- 

 amines solidity. The skin of the hands has many 

 peculiarities. In the palms and on each side of the 

 joints of the fingers, it is furrowed and free from hairs, 

 to facilitate the closing of the hand. The extremities 

 of both fingers and toes are furrowed internally by very 

 beautiful lines more or less spiral ; || and are shielded 

 externally by nails. 



233. These scutiform nails** are bestowed upon man 

 only and a few other genera of mammalia (we allude to 

 the quadrumana which excel in the sense of touch), ff 



G. Bew, Memoirs of a Society of Manchester. Vol. i. p. 159. 



Ch. Hutton, Mathematical Dictionary. Vol. i. p. 214. 



* F. de Riet, De Organo Tactus. LB. 1743. 4to. reprinted in Haller's 

 Anatomical Collection. T. iv. 



f Dav. Corn, de Conrcclles, Icones Musculor. Capitis. Tab. i. fig. 2, 3. 



X B. S. Albinus, Annotat. Academ. L. iii. tab. iv. fig. L 2. 



§ Ruyscb, Thesaur. Anat. iii. tab. iv. fig. i. Thes. vii. tab. ii. fig. 5. 



B. S. Albinus, 1. c. L. vi. Tab. ii. fig. 3, 4. 



|| Grew, Philos. Tratu. n. 159. 



** B. S. Albinus, Annotat. Acad. L. ii. tab. vii. fig. 4, 5, 6. 



ff Namely simiae, papioncs, cercopitheci, and lemurcs, the apices of whose 

 fingers in their four hands are very soft, and marked, as in the human subject, 

 with spiral lines. 



Physiologists have disputed whether the sense of touch is bestowed on any 

 besides man and the quadrumana. In determining this controversy v.e must 

 recollect what was formerly said (81) concerning the difference of constitution 



