122 tringsheim's researches on chlorophyll. 



nature of their included bodies. These all agree chemically 

 in this, that they are non-nitrogenous, and they are visible 

 products of assimilation, derivates, differing from one another 

 jn oxygen-content, of the carbonic acid and water decom- 

 posed in the process, the extent of their oxygenation being 

 determined, on the hypothesis of a single primary assimi- 

 lation-product, by the amount of respiration in the corpuscles 

 as governed by the intensity and colour of light. From the 

 side of chemistry this view is not contradicted, but its 

 admissibility depends on anatomical and physiological 

 considerations. 



The primary reduction-product, of which, by oxidation, 

 the ternary compounds in the chlorophyll-corpuscles are in 

 the Avidest sense derivates, is to be sought for in the drops 

 exuded from the corpuscles after treatment with dilute 

 acid or moist warmth, as these contain all the constituents 

 of the corpuscle sensitive to light, and with strong affinity 

 for oxygen. All the nitrogenous compounds and stable 

 ternary assimilation-products — starch, fat, tannin, &c. — 

 remain intact within the corpuscles. In the exuded mass, 

 hypochlorin, which is the only very sensitive substance 

 besides the colouring matter itself, is present as is known. Its 

 universal occurrence has already been referred to. Wherever 

 chlorophyll occurs it is to be found ; so constant, indeed, 

 is this, that in epidermal cells and hairs of phanerogams, 

 or the cells of phanerogamic parasites, in which chloro- 

 phyll-corpuscles are exceedingly sparsely distributed, their 

 assimilatory activity may be readily proved by the de- 

 monstration of hypochlorin through treatment with acid 

 or other suitable reagent. It is found along with and 

 without the other constituents above mentioned. They may 

 be derived from it; it cannot arise from them. Its sporadic 

 occurrence in the chlorophyll-corpuscles of one and the 

 same cell indicates its employment in assimilation. The 

 accumulation of deposits of formative material, especially 

 starch, in the chlorophyll-corpuscles, increases with age; the 

 hypochlorin, on the other hand, decreases in the green 

 tissue as they grow older. Indeed, the richer they are in 

 these deposits the poorer are they in hypochlorin. All this 

 points strongly to the genesis of these bodies out of hypo- 

 chlorin, and equally so does the constant relation of hypo- 

 chlorin in^ Spirogyra and other Conferva to the amylum- 

 bodies where a causal connection can hardly be denied. 



Hypochlorin, then, is not only universally present as a 

 product of the chlorophyll-corpuscles, but has also a very 

 definite time and place-relation to the formation of the 



