SECTIONAL TRANSACTIONS.— TEXTILES. 413 



laboratory and in the mills. Instruments have been devised for measuring the 

 tension or ' drag ' in the yarn (of the order of ten grams), not only as it leaves the 

 front roller, but as it -winds on the bobbin, the. latter instrument revolving at 6000 

 r.p.m., and being used in conjunction with the stroboscope. 



Mr. J. A. Fraser Roberts. — The Inheritance of Some Colours and Patterns 



in Sheep. 



During the past four years the University College of North Wales, in association 

 with the Animal Breeding Research Department, University of Edinburgh, has been 

 conducting breeding experiments to determine the mode of inheritance of certain 

 colours and patterns in sheep. 



The following characters have been investigated : — 



1. A dominant black in the Black Welsh breed. 



2. A dominant black in the Piebald breed. 



3. A brown modification of black. 



4. The recessive black known in several breeds. 



5. A highly characteristic pattern that has been called ' badger-face ' and which 

 is recessive to white. 



6. Reversed badger-face pattern, in which the colours of the above pattern are 

 exactly reversed ; also recessive to white. 



7. Piebald pattern, found to depend on a recessive factor that only acts on sheep 

 that possess the constitution for self-colour. 



The interrelations of the factors responsible for the production of these colours 

 and patterns are in some cases curious and interesting. Badger-face pattern, reversed 

 badger-face pattern, and recessive black appear to form with white a series of multiple 

 allelomorphs. White crossed to the other three gives white ; badger-face crossed to 

 reversed badger-face and recessive black gives badger-face ; the cross reversed 

 badger-face X recessive black has yet to be made. Dominant black segregates 

 independently of badger-face pattern and is, therefore, presumably independent as 

 regards the reversed pattern and recessive black also. The reversal of pigmentation 

 in the case of badger-face and the reversed patterns is very striking. The form of 

 the pattern is identical down to the smallest details, but those areas that are white 

 in the badger-face are black in the reversed badger-face, and vice versa. This in 

 conjunction with the probable existence of the multiple allelomorphic series already 

 mentioned presents an unusual and interesting phenomenon. The modifications of 

 colour, especially of black to grey and brown, would be of interest in connection with 

 any attempt to develop coloured fleeces for the production of undyed fabrics. 



Mr. J. B. Nichols. — Coloured Fibres in the Fleece. 



Coloured fibres present one of the most serious objections to British wools from the 

 point of view of the manufacturer, and also, in many breeds of sheep, of the breeder. 

 But the presence of pigmented areas on the head and legs is considered highly desirable 

 by the butcher in many localities ; it is a matter of common observation that where 

 the extremities are pigmented there is a tendency towards an admixture of pigmented 

 fibres hi the fleece. The problem of the elimination of these admixed coloured fibres 

 is the most important if the clip is considered as a whole, and observations show that 

 the solution of the problem lies in breeding and selection but is complicated by the 

 influence of external conditions. 



It may be considered that the basic coloration of the animals is determined by 

 genetic factors, and the degree to which the colour is expressed is likewise conditioned. 

 Observations have been made on the Suffolk breed where the darkness of extremities 

 is most marked, and the great problem of the breeder is to limit definitely the 

 pigmented areas. A study of the early coat of the lamb indicates that the first 

 development of all kinds of fibres in this breed is accompanied by and includes 

 deposition of pigment in the fibres ; the lambs are born more or less dark in appearance, 

 and the changes in coloration which follow as the lambs age take place in two 

 directions and at different rates according to individuals. The extremities become 

 darker, while the body area appears to become lighter in general appearance, because, 

 in the latter case, of the gradual shedding of the coarser wholly pigmented fibres, 

 and the lengthening of the finer fibres without further inclusion of pigment. It is 

 possible to estimate the rates of change of gross coloration of extremities and body, 

 and certain bases for selection for the ultimate freedom of the fleece from coloured 

 fibres according to the changes in early life have been obtained. 



