B. i>. i.—mr^. 



THE FIBERS OF LOXG-STAPLF I'l'LAXD 



COTTONS. 



By H. A. Allard, Scieniijic Aitxistant, Cotton Breedhuj Investigatloits. 



UNIFORMITY OF COTTON FIBERS. 



In investigatioiLs in cotton breedintr where an inipiovement in cer- 

 tain lint characters is desired several factors must be carefully consid- 

 ered. Aniont( these, some of the most important are fineness of lint, 

 the relative yield of lint to the total yield of seed cotton, and the uni- 

 formity of length of all the fibers when i)roperly coml)ed out and 

 examined. The last character, uniformity of length, is a most impor- 

 tant one and has much to do with subsecjuent waste and the produc- 

 tion of good yarns in the process of manufacture. 



On Plate II are illustrations of cotton seeds with fibers combed out 

 to show uniformity and nonuniformity in the length of the fibers. 

 The seeds to the left (A) show very poor uniformity and are of the 

 "butterfly" type, as they are commonly called. In marked contrast, 

 the seeds to the right (B) show excellent imiformity as a result of 

 several generations of careful selection. 



APPARENT LACK OF UNIFORMITY AND ITS OCCURRENCE. 



There is an apparent lack of uniformity which deserves consider- 

 able attention from the standpoint of cotton growers and breeders. 

 Plate III illustrates this character, although it is more strikinglv 

 brought out in the operation of detaching the seed from the lock. 

 From the illustration there would appear to be a great lack of uni- 

 formit}", due to a group of fibers about twice the length of the general 

 covering. This group arises from the center of the main body of 

 fibers or, often, from those having a point of attachment near the 

 larger end of the seed. This character is usually associated with the 

 finer, more crinkly t3'pes of long-staple cottons, such as the tine, long- 

 linted Egyptian and Sea Island varieties and the long-staple Upland 

 varieties — Griffin, Allen, Cook, etc. It is a character which becomes 

 more apparent as a variety is being rigidly selected generation 

 after generation for finer, longer staple. This has been well illus- 

 trated in the improvement of the lint characters of the Russell 

 variety and, to some extent, the Jones variety. The orginal condition 



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