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power to bring out the usual double contour line, and they 
bad no action, singly, on polarised light, although they became 
a little luminous in a mass of many. 
The growing cotton fibre is an elongated cone with a 
hemispherical apex, and, of course, a circular transverse 
section. Each hair is a single cell. I have sought in vain, 
with all powers and every kind of illumination that I thought 
likely to render it visible, for any section or transverse 
division in the hairs, and I have been equally unsuccessful 
in my search for spiral fibres, which Mr. O’Neill says he found 
in cotton by means of re-agents, and I believe I am justified 
in saying that spiral fibre did not exist in any cotton hairs 
hitherto examined by me. But I have yet to examine pods 
of a later growth, and spiral fibre may yet appear, but I must 
confess I do not expect it. 
I have not seen any twist in growing fibre, and, notwith- 
standing the pressure to which the hairs are probably exposed, 
I have seen no flattening from this cause, but the hairs of 
course collapse and become flat when from any cause the cell 
contents are absent. From sections I have made and examined I 
believe that in the younger pods the hairs wind round the seeds ; 
in the more advanced stages the hairs of neighbouring seeds 
intermingle, and this may account for the bent and twisted 
appearance of dry cotton, that is, in some degree; but the 
principal cause will doubtless be found in the desiccation of 
the cotton after it is exposed to the sun by the bursting of 
the capsule. 
I must not omit to mention that when by pressure a portion 
of the contents is expelled from the cotton hairs, it frequently 
appears in the form of small spheres, in which an active 
molecular movement of granules is seen, just as in the mucous 
corpuscles from the mouth, from which, in appearance, they 
only differ in their larger size. 
I have seen in some dry Sea Island cotton, with a iVth 
and polarised light, what Mr. Sidebotham (was it he?) 
