Fibres. 



14 



.(January, 1910. 



of the cavities in the form a yellow- 

 green emulsion, the particles of which 

 are in lively motion. Strong sulphuric 

 acid dissolved the secretion to a beauti- 

 ful blood-red solution \* A sample of 

 freshly grown cotton seed was examined 

 under the microscope in the laboratory 

 in February, 1908, when it was found 

 that the secretion in the resin cavities 

 appeared clear brown instead of olive- 

 green, as stated above. Treatment with 

 sulphuric acid gave a very beautiful 

 crimson solution. On the other hand', 

 when a sample of seed which had been 

 kept in the laboratory for some years 

 was examined, it was found that the 

 contents of the resin cavities were olive- 

 green, as described above. Treatment 

 with sulphuric acid resulted in the 

 formation of a blood-red colouration as 

 stated, but less intense in colour than 

 with new seed. 



From these observations it appears that 

 the contents of the resin cavities under- 

 go change on keeping, either by oxida- 

 tion or other means, whereby they are 

 changed from a claar brown to a dark 

 green. 



This was subsequently verified by ex- 

 amining, after a lapse of fourteen months) 

 seeds of the sample on which observa- 

 tions had been made when in fresh con- 

 dition in 1908, when it was found that 

 those seeds which had not undergone 

 other changes now possessed resin cavi- 

 ties with dark-green contents. Hence 

 it appears probable that Hanausek's 

 observations were conducted on old seed. 



Further, it was found that when seed 

 of considerable age, of which the resin 

 masses had become green, was crushed 

 and mixed with water, the resulting 

 mash was of a bright-green colour, ex- 

 actly resembling the effect which origin- 

 ally called attention to the phenomenon 

 in the case of the sample of crushed 

 cotton seed first examiued. (It is of 

 interest in this connection to note that 

 the l'esin waste from l^efining cotton 

 seed oil is used for the production of a 

 green dye.) 



On cutting open and examining a 

 number of fresh cotton seeds, it is 

 generally found that a few of them 

 are discoloured, being brown inside. 

 This discolouration may vary consider- 

 ably in extent, all stages being exhi- 

 bited, from a slight to a complete 

 change of colour. When thin sections 

 of seeds affected in this way were ex- 

 amined under the microscope, it was 

 found that the cell-walls were stained 

 brown, and, in some instances, much 

 disintegrated, and throughout the stain- 



* Winton's Microscopy <>j Vegetable Food*, p. 209. 



ed area numerous oil drops were distri- 

 buted. It appeared that the brown 

 staining was in all probability due to 

 the bursting of the resin cavities 

 already mentioned, whereby the con- 

 tents became distributed throughout the 

 body of the seed. 



It was thought that possibly this 

 might have been due to injury to the 

 seed by the gins*, but the fact that the 

 percentage of seed affected in this way 

 tends to increase on keeping, would 

 appear to negative this suggestion. 

 Thus a sample of seed, which in February, 

 1908, showed a percentage affected in 

 this manner of 34, presented, eight 

 months later, 66 per cent, of seed simi- 

 larly affected. It is interesting to record 

 that this increase corresponds approxi- 

 mately with the coincident decrease in 

 the percentage of germination. 



It is not clear whether the death of 

 the seed was connected with this ap- 

 pearance, though it seems likely to 

 have been. If it was, it yet remains 

 to be decided whether it was the cause 

 or the result of the phenomenon. 



(B.) Effects of Storage on the Germin- 

 ating Power of Cotton Seed. 



That cotton seed, on being kept, tends 

 to lessen in its percentage of germin- 

 ation is a well-known fact. To investi- 

 gate this, a quantity of fresh seed was 

 taken in February, 1908, stored in the 

 Government Laboratory for the Lee- 

 ward Islands, and periodical germin- 

 ation tests were conducted on it. 



The results are given below: — 



Date. Germination, per cent. 



February 24, 1908 51 

 June 3, ,, 49 



September 14, „ 32 

 November 5, ,, 36 

 April 24, 1909 8 



The seed was stored in a covered 

 wooden box liued with brown paper. 

 The germination tests were performed 

 on 100 seeds ; the germinator used was 

 of the ordinary type, and was sterilized 

 in every test by boiling before use. 

 The seed used was from Centreville 



* Injury by the gin may be sufficiently severe 

 so that it is easily seen or that its effects are 

 manifest in a short time. On the other hand, 

 an injury from this cause, or from any other 

 cause, such as the puncture produced by a cot ton 

 stainer or other insect, might be so slight : hat 

 it could never be detected as an injury to the 

 seed, and still be sufficient to liberatj the enzymes 

 which cause the changes in the substance of the 

 seed. The action of enzymes being progressive and 

 eumu'ative, the results in deterioration and in de- 

 creased geaminatiug power would be similar to those 

 obtained by Mr. Tempauy.-Ed. W. I. B, 



