168 Fleeces of certain Primitive Species of Sheep 



the whole circumference of the fibre in striking contrast to the surface 

 structure of a hair (PI. II, Fig. 6 a, b, c). 



In the majority of wool-fibres no medulla could be identified contain- 

 ing air-spaces, but in a few definite air-filled central areas were seen 

 (PI. II, Fig. 6 d). 



The Fleeces of Other Species of Sheep. 



For purpose of comparison the hair and wool of 0. ammon hodgsoni, 

 0. mnmon ammon, 0. vignei, 0. montana, and 0. orientalis were examined. 

 Save for certain minor unimportant differences, all were identical in 

 structure and did not differ from the hair and wool of 0. amnion poli. 



In the case of 0. orientalis, however, the character of the inner coat 

 was remarkable in that instead of the fibres forming a much entangled 

 mat (PI. II, Fig. 7 b) as in the case of the other fleeces, they formed 

 natural locks very similar in form to those of the wool of the modern 

 breeds (PI. II, Fig. 7 a). I am indebted to Professor Ewart for calling 

 my attention to this interesting and perhaps important fact. Of all the 

 primitive wools this most resembles in disposition the wool of commerce 

 of to-day. 



The two kinds of fibres in the fleeces of the primitive species of sheep 

 were absolutely distinct and no sort or grade of intermediate fibre was 

 found. Careful search for a fibre of intermediate character was made 

 but without success, each fibre was either hair or wool, definitely and 

 unmistakably. Thus the fibres of intermediate character found in certain 

 modern fleeces cannot be regarded as transitional forms and the question 

 as to whether hair and wool are different in their origin and development, 

 or whether they result from the divergent development of a common 

 type of fibre of intermediate character cannot be answered. The exact 

 relation of hair and wool must be sought in other mammals. 



The hair and wool of the primitive species of sheep may be accepted 

 as the typical examples of these fibres and as standards to which the 

 fibres in the modern fleeces may be referred. 



SUMMARY. 



1. The fleeces of certain wild and primitive species of sheep were 

 examined. 



2. That of Marco Polo's sheep was found to be the one most suitable 

 for examination, since samples of both summer and winter coats were 

 available. In the former coat there was hair only and still growing. In 

 the latter coat it was mostly full-grown and much less pigmented. The 



