Study of Spifogyra >:iti,ta. 225 



to diminish, since the tannin formed seems to be diffu 

 into the water. Unfortunately this could not be deter- 

 mined by micro-chemical tests, since the resin is so closely 

 bound with the chlorophyll. But the oil drops exuded by 



the bauds probably represent the material which, when the 

 cells are not subjected to such a stimulus as conjugation 

 affords, yield with the tannin the resinous body. 



The carbohydrates of the cell show decided modifications. 

 As has been already mentioned the glucose increases, ap- 

 parently at the expense of the starch. There is always, 

 however, a considerable amount of starch in the cell along 

 with the glucose. 



The behavior of a vegetating cell with Fehling's solution 

 has already been discussed, the cell in this case having 

 only a small amount of glucose. In the conjugating cells, 

 even before the tubes have reached any great size, the 

 quantity of glucose has so increased that the cuprous oxide 

 deposit appears quite black under the microscope. When 

 the bands of the cell begin to change their normal position 

 the great mass of glucose is seen to be directly in front of 

 the tube, and to be pushing into it. This mass of glucose 

 persists in the cell, and when the giving cell transfers its 

 contents, the glucose in large quantity can still be detected. 



No trace of cane sugar could be found in these cells. 



Every one who has handled fresh Spirogyra is familiar 

 with the smoothness and apparent sliminess of the mass of 

 threads. This is readily explained by the large amount of 

 mucilage united with the cellulose. In the conjugating 

 material this sliminess has largely disappeared. The 

 threads are far more adherent than at other times, and show 

 a strong tendency to collect and hold the small particles of 

 disintegrated organic matter with which they come in con- 

 tact. There is here a modification of the cell wall, causing 

 an increase of the gum, hence rendering the cell more 

 adhesive. 



The proteid of normal Spirogyra gives off very readily 

 trimethylamine. The conjugating material did not yield 



