F. A. E. Crew 165 



But classed according to the length and structure of the hair there 

 are two types also. One is relatively short and curled and is hidden by 

 the longer, coarser, straighter kind. These two types of hair, because of 

 the difference in their length and disposition, form two coats: an inner 

 one of fine, curly fibres, forming an open-meshed mat snugly appUed 

 to the surface of the skin, and an outer one of stout, up-standing fibres, 

 projecting well beyond the inner coat. 



The two coats appear to serve different functions and this is asso- 

 ciated with very distinct differences in structure. The outer one shields 

 its wearer from excessive heat and cold, from wet, and from injurious 

 contact with objects generally. It is cold- and heat-excluding, the 

 general direction of its component fibres is such that it forms an efficient 

 downward watershed, draining off the rain as it falls ; its fibres present 

 a surface upon which snow does not readily find a lodgment; and it pro- 

 tects the curly, delicate, fine hair of the inner coat from entanglement in 

 thorny thickets. 



The inner coat is heat-retaining in function, for in its meshes air is 

 held. The inner coat is the wool of commerce. Many other mammals 

 also possess this coat and it is a matter of conjecture why man chose 

 the sheep as the source of his supply. 



I am indebted to Professor J. Cossar Ewart, F.R.S., of the University 

 of Edinburgh for the samples with which this study was made, and to 

 Major H. J. W. Bhss of the British Research Association for the Woollen 

 and Worsted Industries for much helpful criticism. A grant from the 

 Carnegie Trust has enabled me to illustrate this paper with appropriate 

 plates. 



THE FLEECE OF 0VI8 AM HON POLL 



Marco Polo's "exceeding great wild sheep, having horns, some of 

 them six spans long," are found on the mountain ranges of the Pamirs 

 — "the roof of the world." They have been shot 18,000 feet above sea- 

 level. The climate of this region is very rigorous, with long winters, rain 

 and snow and bitter winds, but the water-courses and vaUeys are rich 

 in mountain grasses, and even on the high passes in March snow is rarely 

 so deep as to prevent the herds of the Kirghiz from finding pasturage. 



Two samples from the summer and winter coats respectively were 

 available for examination, and both were taken from the mid-dorsal line 

 between the shoulders. 



The summer coat (PI. I, Fig. 1, left) on inspection showed one kind of 

 fibre having the general appearance of hair as opposed to wool. But 

 classed according to length and colour, there were three groups ; 



