124 



SENSE OF TOUCH. 



Fig- 40 - 



s c 



Fig. 41. 



rest of the derma. Secondly. Around the nipple of the white woman, 

 the superficial layer of the derma presents the same granular appear- 

 ance as the pigmental membrane of the coloured races. And thirdly. 

 The pigmental layer around the nipple of the white woman is placed, 

 afc in the coloured races, under the two cuticles. 



Modern histologists consider the 

 epidermis to be composed of a series 

 of flattened, scale-like cells, epider- 

 mic cells, which, when first formed, 

 are of a spheroidal shape; but gra- 

 dually dry up. These form various 

 layers. According to Mi Raspail, 1 it 

 Vertical Section of the Cuticle from the consists of a collection of vesicles de- 

 prived of their contents, closely ap- 



a. Deep cells, loaded with pigment, b. Cells ^i;^ fnrrpfVior rlri^rl nnrl rlivnwnnflF 



at a higher level, paler and more flattened. pU^d tOgCtner, dried, and tillOWn 



c. Cells at the surface scaly and colourless as i n the form of brannj SCaleS. He 

 in the white races. Magnified 300 diameters. _ , - , 



regards it as the outer layer or the 

 corium. 



The epidermoid tissues have the 

 simplest structure of any solids. 



Analysis has shown, that the che- 

 mical constitution of the membranous 

 epidermis of the sole of the foot is 

 the same as that of the compact horny 

 matter of which nails, hair, and wool 

 are composed. 



2. The corpus or rete mucosum, 

 rete Malpighii, mucous web, is gene- 

 rally regarded as constituting the 

 next layer. It was considered by 

 Malpighi to be mucus, secreted by 

 the papillae, and spread on the surface 

 of the corpus papillare, to preserve it 

 in the state of suppleness necessary 

 for the performance of its functions. 



Section of the Skin. In this rete mucosum, the colouring 



i. cuticle, showing the oblique lamin. of tt ? ^ dark races seems to ex- 



which it is composed and the imbricated dis- jgt. it IS blaCK in the AlHCan, Or 

 position of the ridges upon its surface. 2. ,-, ^ T\,-I j 



kete mucosum. 3. TWO of the quadrilateral rather in the Mmopian; and 



papillary masses seen in the palm of the hand rtr .l rt ,- I . rv/ l i-r, -fli/^ miilattn 2 



or sole of the foot ; they are composed of COlOUred in TOO mUiatlO. 



minute conical papillae. 4. Deeper layer of considers it tO be COniDOSed of four 



the cutis, the corium. 5. Adipose vesicles ; , . . r . , . 



showing their appearance beneath the micro- layei'SJ DUt thlS notion IS not admit- 



scope. 6. Perspiratory gland with its spiral ,11 A_ J i 



duct, as seen in the palm of the hand or sole ted by anatOmiStS, and Scarcely COn- 



of the foot. 7. Another perspiratory gland ppy-nc flip DTPSfnt inouirv 1V4 Bre- 



scaip. s. TWO hairs from the scalp, enclosed schet affirms, that there is a special 



in their follicles; their relative depth in the , 7 ./. 



skin preserved. 9. A pair of sebaceous glands " CnromatOgenOUS Or COlonjlC appa- 



opening by short e rat ^ f()r pro ducmg the Colouring 



1 Chimie Organique, p. 245, Paris, 1833. 



a Sir E. Home, Lect. on Comp. Anar., y. 278. 



3 Reclierches Anatomiques sur le Systeme Cutane de rHomme, Paris, 1811. 



