98 PHYSICAL INVESTIGATION. [PART I. 



Negro blood from that of the European. T. W. de Miiller 1 

 observes that in hot climates the arterial blood of white and 

 coloured men also resembles venous blood, in consequence of 

 the greater quantity of carbon contained in it ; and it has been 

 asserted that the predominance of the latter induces mental in- 

 dolence. The choleric and phlegmatic temperaments only are 

 said to prevail among Negroes. The greatly developed genitals 

 exhibit frequent turgescence. The glandular system is much 

 developed (Primer) . The stomach has a rounder shape (Som- 

 mering) . 



The skin affords to the Negro a greater protection agains 

 the rays of the sun than to the European, as, exposed to the 

 sun for a longer time, it is not blistered; it is also per- 

 ceptibly thicker on the whole body than that of the European 

 it is always cool and velvety to the touch. With regard to th< 

 latter point, the savage natives of Central Africa are said to 

 form an exception, as their skin becomes wrinkled and chapped. 2 

 It is more or less black according to the deposition of the pig- 

 ment, which (according to an analysis not entirely to be relied 

 upon), consists of nine-tenths of carbon to one-tenth iron and 

 fat (De Muller), and is found in the common cells of the 

 mucous layer of the epidermis, and not in special pigment cells, 

 whilst the dermis of the Negro is like that of the European. 3 

 This pigment, which is wanting in the Negro foetus, is also 

 deposited in the mucous layer under the nail, 4 and in the mem- 

 branes of the brain (De Muller), exceptionally, though rarely, also 

 on the gums and the velum palati, 5 and upon the tongue (Primer) . 

 The palms only, and the soles of the feet, are of a lighter 

 colour, the first, frequently of European whiteness (Burmeister) . 

 According to Flourens' former opinion there was said to exist 

 between the epidermis and dermis an organ absent in the white, 

 which contained the colouring matter ; he has, however, now 

 adopted the prevailing opinion that there is no difference in 



1 LOG. cit., p. 45. 



2 D'Escayrac die Air. Wiiste und das Land der Schwarzen, p. 186, 1855. 



3 Kolliker, " Microscop. anat." 



4 Beclard, "Anat. generale," p. 309. 



5 Arnoux, " Bullet, soc. ethnol.," p. 52, 1847. 



