33() PEINClPAL SIR WILLIAM TURNLH ON 



shades of brown. In each hair examined a distinct black axial medulla was present, 

 which frequently extended for a considerable distance unbroken, but sometimes it 

 was interrupted by relatively long intervals, though at others with only short 

 gaps, and the cortex constituted the body of the shaft. In places the medulla 

 was so broken up that the outlines of the cells could be seen. 



Solomon Islands. — The hairs were mostly coated with a black tenacious material, 

 which was removed with difficulty, and until this was taken off the hair was black 

 and opaque. The cortex of the hair was then seen to be dark brown with pigmented 

 spots and longitudinal dark lines. In some hairs only cortex and cuticle were distinct, 

 but others possessed a black medulla which was frequently broken into short sections. 

 The diameter of the shaft ranged from '0500 to '0750, and that of the tip was '0200. 



New Guinea. — The specimens were cuttings. In the locks from Rubi, Geelvink 

 Bay, the hairs were twisted; the broader diameter of the shaft was about '07 mm., 

 the narrower '05 mm., the hair index about 63 (fig. 10). The cut ends measured 

 in breadth about '05 ; the diameter of the pointed tip of one hair measured was 

 '02 mm. The individual hairs gave characteristic views of the light to dark brown 

 fibrous cortex, and a dark axial medulla was also present. The medulla had a 

 strong disposition to break up into fragments, so small indeed in places that the 

 individual cells could be recognised without difficulty. The cortex was occasionally 

 split longitudinally. 



In the cuttings of human hair from a dance mask from the Papuan Gulf the cut 

 ends were on the average about '05 mm. in breadth, but the free tip of a hair was 

 only '0225 mm. The shaft showed the customary broader and narrower alternations 

 in diameter due to the twist present in woolly-haired races ; measurements ranging 

 from '0875 to '0525 were noted, and a mean hair index 70 was computed. Under 

 the microscope the hairs varied in their depth of colour, some were so opaque that 

 their structure was ill defined, others were a deep brown, others a much lighter 

 brown. In those lighter hairs the fibrous structure of the cortex was recognised, 

 in some of which an axial dark medulla somewhat interrupted was distinct, whilst 

 others again showed no trace of medulla. 



Negro. — In transverse sections through the cutis of the scalp, I measured the 

 diameter of several hair follicles which ranged from 0'1 mm. to '0275, so that in 

 the same plane of section a great diversity in the breadth of the follicle was seen. 

 The divided cornified hairs lying in the follicles were also measured. It was excep- 

 tional to find one circular in outline or even approximately so. As a rule they 

 had two diameters, one definitely longer than the other, so that the hair was 

 flattened laterally and the section was either a wide or an elongated ovoid, with 

 sometimes a kidney-like depression on one aspect. The breadth or longer diameter 

 of the section of hair in the larger follicles ranged from '075 to '0375, whilst the 

 depth or shorter diameter was from '045 to '0325 mm.; the index computed from 

 these dimensions was 51. The ends of the shafts cut from the scalp averaged 



