84 MANAGEMENT AND FEEDING OF SHEEP 



as shown later. This peculiarity of fleece is confined to the 

 fine wooled breeds. 



The benefits from such closure have already been 

 touched upon. Sheep that are thus protected can endure 

 exposure to rain, and especially to cold rain, very much 

 better than sheep not thus covered. This furnishes one 

 explanation of the superior hardihood of the Merino 

 types. The only avenues through which any dirt can 

 penetrate the wool are the openings between the glued 

 masses, and these are so minute as practically to exclude 

 dirt. Should it enter between the locks or masses, the 

 outward movement of the yolk continually tends to eject it. 



Closure in the fleece is largely the outcome of breeding 

 and selection. It is not possessed equally by the Merino 

 breeds, nor even by individuals of the same breed or class. 

 It is also much influenced by food. Sheep that are well 

 fed will possess more closure of fleece than others of sim- 

 ilar breeding when on a spare diet. This follows from 

 the plentiful and suitable food supplies and a sufficiency 

 of yolk. Closure is not to be sought to the extent of 

 gluing all the fibers together over any considerable area 

 of the body, as this would make a covering so warm as to 

 be unendurable in the summer season. The gluing is 

 rather to be confined to small aggregations of fibers in a 

 way that does not interfere with the escape of body heat 

 through radiation. 



Felting in wool Felty wool is that in which the 

 fibers have a tendency to felt together on the sheep's 

 back. In the aggravated form it is known as cots or cot- 

 ted wool. The fibers so felt together that by shearing 

 time portions of the fleece or all of it is so completely 

 felted or matted that it can be lifted up by a single lock 

 without parting asunder. It more generally develops in 

 the winter season, when the sheep are on a dry diet. Such 

 a fleece has a relatively low value and should not be sold 

 with other wool. 



Cotting is caused primarily by an absence of yolk. In 



