258 Pennington — A Chemico-Physiological 



of the chlorophyll bands, the inner layer of protoplasm 

 and the nucleus. The outer protoplasmic layer, however, 

 was unaffected and still adhered closely to the wall of the 

 cell. The balled mass was generally pulled to one end or 

 close to the sides of the cell. The many crystals were in 

 this way left quite free in the unoccupied space of the cell, 

 and could be easily studied. None were seen in the balled 

 material, hence it was inferred that these bodies lie between 

 the two protoplasmic pellicles. 



Summary. 



1. An analysis of Spirogyra nitida shows that the chlo- 

 rine and sodium content of the ash is comparable with the 

 chlorine and sodium content of the salt-water algae. The 

 dry matter yields all the usual organic plant constituents, 

 tannin being in specially large quantity. 



Micro-chemical analysis reveals crystals of calcium tar- 

 trate, as well as those of calcium oxalate, side by side in 

 the cell. 



2. The trimethylainine, which is readily evolved from 

 5. nitida, is apparently closely connected with, and aids in 

 the formation of a proteid body. It is not evolved when 

 the plant is exposed to light, but is detected in darkened 

 material. This amine accumulates in the de-starched cell, 

 but does not seem to result from the decomposition of 

 lecithin. 



3. Conjugating cells show a chemical composition which, 

 in almost every essential differs widely from that of the 

 vegetating cell. The behavior of the tannin, and its 

 marked increase in quantity is now striking ; as is also the 

 presence of oil droplets, which are found free in the cells. 



4. Under colored screens, furnishing light of definite 

 quality, the chemical composition of 6". nitida differed ac- 

 cording to the light rays which it received. 



(a) Violet rays prevented almost wholly the hydration of 

 starch, and soon killed the plant. 



(6) Blue rays gave an imperfect hydration, but sufficient 



