226 Pennington — A Chemico-Physiological 



the characteristic fishy odor to the hands of the operator, 

 nor to the vessels containing the air-dried substance, in any- 

 thing like the quantity usually observed. Some of the 

 threads, as free as possible from vegetating cells, were accord- 

 ingly heated with potassium hydrate. The odor of trime- 

 thylamine was plainly detected, but comparison with a like 

 quantity of vegetating threads, under the same conditions, 

 showed that the amine was relatively in very small amount, 

 and in all probability this was due entirely to the admix- 

 ture of vegetating cells, from which it was impossible to 

 free the material. 



Morphological study has demonstrated that the cellulose 

 wall is intact over the ends of the connecting tubes until 

 after they have met. Watching closely the behavior of the 

 giving cell, it was noticed that after the mass of material 

 had begun to enter the tube a clear, refractive, colorless 

 layer of protoplasm was sent in advance. It was granular 

 in composition and very motile. The dividing wall of the 

 closely pressed together tubes having been reached, the 

 substance remained flattened against it for about one-half 

 minute. The wall then suddenly dissolved, and the trans- 

 fer of material from one cell to the other began. 



This clear particle of protoplasmic material behaves like 

 a cellulose ferment, and doubtless contains such an enzyme. 

 Whatever be its nature it certainly is the active agent in 

 dissolving the septum between the cells. It can be easily 

 seen that a simple rupture does not take place, the passage 

 being clearly cut with sharp boundary lines, and of the 

 same size as the protoplasmic mass which pressed against 

 the cell wall. The dissolved area may be in the centre of 

 the plate or at one side. It is, however, fully formed by 

 the substance above described, and does not increase in size 

 during the passage of the remainder of the cell contents. 



Starch passes over as such. Treatment with iodine shows 

 blue masses in the act of transference. Many of these are 

 too large for single grains. It would seem, therefore, that 

 the pyrenoid, with its surrounding starch granules, is only 



