928 PROCEEDINGS OF SOCIETIES. 
I should perhaps say translucent, for the cotton hairs do not seem 
ever to be transparent. 
In a more advanced stage the seeds were covered with hairs 
which contained numerous minute granules floating in a very 
fluid and colourless mucus. An active rotation of the cell con- 
tents, exactly like that in Nitella, was seen in all the hairs that 
had not been injured by pressure, and continued for a considerable 
time, at least half an hour. I found it could be seen with Ross’s 
half-inch and the higher eyepieces, but I used chiefly a =4;th. 
In a pod apparently somewhat older the appearances only 
differed by the cell contents, which I have called colourless mucus 
above, becoming thickened, and the granules somewhat smaller, 
so that we had a fine granular mucus of a pale buff colour. 
As the pod becomes older the cell contents appear to increase 
in density and rotation to cease; at least I have not seen rotation 
unless in the hairs of young seeds, z.e., seeds from young pods of 
perhaps from two or three to ten or twelve days’ growth. I have 
not, unfortunately, been able to learn the exact age of the pods. 
On Saturday last I plucked a fine pod of Queensland cotton 
(growing in the garden of a friend) that was supposed to be nearly 
full grown, and was upwards of two inches in vertical diameter. 
In the hairs of this I found generally, but not always, a considerable 
amount of secondary deposit, made evident by the thickening of 
the walls and by its action on polarized light. But in the hairs of 
younger pods there was nothing of the kind, and the walls were so 
thin as scarcely to afford evidence of their presence, it requiring 
considerable power to bring out the usual double contour line, and 
they had no action, singly, on polarized light, although they 
became a little luminous in a mass of many. 
The growing cotton fibre is an elongated cone with a hemi- 
spherical apex, and, of course, a circular transverse section. Hach 
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, notwithstanding 
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 
