12(5 THE SENSE OF TOUCH IN ANIMALS 



of the hind foot made across some aberrant longitudinally- 

 placed papillary ridges. Under these are seen well-developed 

 papillae of the corium markedly larger and more prominent 

 than are found in sections from skin where there are no papillary 

 ridges. 



Aniliropopiihecus troglodytes (Fig. 158). — Transverse section 

 from an interdigital pad on the palmar surface of the forefoot, 

 shoAving large clear, papillary ridges, low, thick Driisenleisten, 

 with bifurcated, low and pointed papillae of the corium. 



Fig. 159. — Transverse section from pad at the base of D. 1 

 on the palmar surface of the forefoot, shows long, close-set 

 papillae of the corium, and well-marked Driisenleisten, free 

 surface of the epidermis being little differentiated. 



Fig. 160. — Longitudinal section from tip of terminal phalanx, 

 showing low, papillary ridges of digit of hind foot, low papillae 

 of the corium, and small Driisenleisten. 



Man (Fig. 161). — Longitudinal section from the terminal 

 phalanx of the fourth digit of the hand. Papillary ridges low 

 and somewhat worn down and showing distal imbrication. 

 Papillae of the corium double and very marked with Driisen- 

 leisten, moderately developed, dividing the papillae. One 

 group of these elements belongs to each papillary ridge. 



Fig. 162. — Longitudinal section from fifth digit, terminal 

 phalanx of hand, also showing distal imbrication, and papillae 

 of the corium more pointed and less clearly defined. 



Fig. 163. — Transverse section (resembling Fig. 157 of Simia 

 satyrus) across the dorsal surface of the terminal phalanx of 

 the fourth digit taken near the root of the nail. This is made 

 at right angles to certain aberrant longitudinally-placed papillary 

 ridges. On the right side of the section are these ridges, and 

 underneath them very numerous pointed, closely-set papillae 

 of the corium ; on the left side are no papillary ridges and no 

 papillae of the corium are to be seen. This section shows particu- 

 larly well the connection between papillary ridges and papillae of 

 the corium. 



Fig. 164. — Longitudinal section through the pulp of the 

 terminal phalanx of the second digit of the foot. Imbrication 



