80 T1UCI10LOGIA MAMMALIUM; 



to all persons of whatever nation or country who have silky, dirty or reddish- white colored 

 pile, a pale reddish-white skin, red pupils and weak sight. The number of these indi- 

 viduals is not great; Van Amringe* computes that they do not exceed one in a million of 

 the inhabitants of this earth ; yet Dr. Prichard treats them as a distinct race. In his 

 researches on the physical history of man, he divides the human family into the Melanic 

 or black-haired, the Xanthus or yellow-haired, and the Albino or W 7 hite-h aired! 



No. 1. Examination and Description of the Pile of the head of the White Albino, Mary 

 McWilliams, aged twenty-Jive, born in Ireland. Specimen presented by Dr. Klapp, of the 

 Pennsylvania Hospital, in the city of Philadelphia, the 2d of March, 1849. 



Length, (artificial,) 4 inches; shape, oval, compressed, tapering; for example, a yoxing 

 filament, one inch long, has for its diameter, at the posterior extremity, ^ by ^ 7 , in the 

 centre, ^^ by |^, and at the apex, -5-^-$ of an inch; color, white, with a slight tinge of 

 yellow; lustre, ^considerable ; direction, flowing; inclination, we had no means of ascer- 

 taining. 



Ductility, Elasticity and Tenacity. One inch of filament, (the Barometer being 39, the 

 Thermometer being 72, and the Dew-point being 68,) 



With 170 grains stretched -^ of an inch, and when the weight was removed the elasticity 



was entire. 



" 220 " " 8<V 



" 270 " " -gV " minus -Jg- of an inch. 



" 320 " " Jg- " " " 



" 470 " " 9<V 



" 520 " " -gV 



" 570 " " ft " " 9% 



" 620 " " || " " || 



" 670 " " || " " || 



" 720 " " # " " ff 



" 770 " " || " " || 



" 820 " " || " " H 



" 870 it broke. 



Fracture, abrupt; button, sheath and follicle, we had none to examine; shaft, uneven, 

 bulged, flattened and sunken in different places; cortex, transversely striated the whole 

 length of the shaft ; ribbons of cortex, artificially detached from the body of the shaft, 

 exhibit transverse divisions, the largest portion measuring ^^ of an inch; intermediate 

 fibres, white, lustrous, and with a diameter of from 5- -Air * TTrVir f an i ncn > the mass of 

 fibres divided into sections or nodes ; when the shaft is artificially crushed, these fibres are 

 distinctly seen; they are white, lustrous, and partially separated; but no canal or coloring 

 matter is to be observed through the interstices! ; centre, has a canal for the coloring 



* In Natural History of Man, p. 71. 



t The same experiment was tried upon the other specimens, and the same results ensued ; but when the wool of a pure 

 negro, or the black wool of sheep, was similarly treated, the piles were black. 



