COTTON FIBRE 27 



a thin lining of protoplasm, and at this stage indications are given 

 of vigorous growth. The deeper-seated tissues of the seed, charged 

 with nutritious matter, are now drawn upon in the metabolism 

 of cotton (cell) formation. As a consequence, the coats of the seed 

 gradually harden into a firm shell, covered with the now perfect wool 

 coating. But it is most significant to record in this connection that 

 the cotton growth is neither constant nor uniform. 



Some of the cells would seem to grow more rapidly, others to Irregu- 

 start growth much later. In time the hairs at the pointed extremity 

 of the seed become approximately one length, but shorter, as a rule, 

 than those at the rounded end ; and, moreover, in many instances the 

 seed comes to possess an under fleece called the fuzz, owing to a 

 certain percentage of the cuticular cells being only partially elongated 

 while others are considerably more produced and formed into the 

 outer fleece, the floss proper. (Cf. pp. 7-8, 41.) 



Fuzz and Floss. High cultivation cannot, however, be upheld as F UZZ and 



flo^s 



completely eliminating the fuzz and producing what is called the 

 naked-se'eded condition, since there is at least one truly wild species 

 (never recorded as met with under cultivation, namely G. Kirkii) in 

 which the seed is practically devoid of any trace of an under fleece 

 though possessed of a fairly copious red-coloured and easily 

 removable floss. 



It is of vital importance commercially that the floss or cotton Uni- 

 be as near as possible of one length, and as near as possible of one formi *7 

 age ; hence the conditions that tend to uniformity in both these 

 directions are quite as important as those that favour elongation 

 long staples. In the selection of stock with a view to improve- 

 ment of staple, therefore, uniformity of growth or elongation, and 

 uniformity of age or maturity, are highly essential qualifications. 



No mature cotton (cotton where growth has ceased) that manifests 

 a high percentage of short or imperfectly formed hairs, intermixed 

 with fully-formed floss, can be regarded as of much value. 



Formation of Cellulose, When growth is approaching completion Thicken- 

 it will be seen that a sort of thickening of the protoplasm has taken ce ii-wall. 

 place, the nucleus has gradually disappeared, and secondary changes 

 have been set up that have resulted in a strong cellulose wall. But 

 here again these changes do not take place uniformly in all the cells, 

 nor to the same extent throughout individual cells. 



Moreover, within the caverns of the young growing cells there are Cell- 

 now seen very minute coloured particles that in time aggregate into 



