80 pringsheim's researches on chlorophyll. 



Gymnogramme, and in leaves of species of Selaginellecs. 

 Lastly, amongst Phsenogams, in leaf tissues of Taxus, 

 Zostera, Vallisneria, Elodea^ Ceratophyllum, Heliconia fari- 

 nosa, Tilia, and Ampelopsis. This effect is not observed in 

 plants that are not chlorophyll-green, e.g. in Phycochro- 

 7nace(je, D'latomacece, Phoeosjmrece, Facacea, Floridece, and 

 Fungi, — traces of it only were observed in some stages of 

 their life-history in diatoms, — although the exudation of 

 colour drops after warming in water may be observed. The 

 VaucheriecR are a curious exception, as in them frequently no 

 trace of the action is visible. 



After a short exposure to the acid, in from six to sixty 

 hours, the rust-coloured masses begin to change in appear- 

 ance. They become angular and Spikey, and form on the 

 surface of the corpuscle more or less broad scales or nests, with 

 an indistinct crystalline texture, from which sharp-edged and 

 pointed prolongations develope (figs. 2 6 and 5), or they 

 form cloud-like precipitates with firmer embedded pieces 

 (fig. 2 a). At a later period still further changes take place, 

 and these go on equally well if the specimen be left in the 

 acid or removed to pure water. From the irregular masses 

 are developed short, stiff, straight (often rhombic), or crum- 

 pled or wavy rods, like the so-called rods of the waxy coating 

 on Musace-ce, having blunt or pointed ends (figs. 15 and 16) ; 

 or the productions are long, firm, straight, or coiled needles 

 (figs. 6, 7, and 17) ; or delicate flexible filaments (figs. 8 and 

 9). No differentiation is observed in these crystalloidal 

 masses, except occasionally in some of the rods, when, owing 

 to a slight condensation of the periphery, a double contour 

 is shown. 



As the rust-brown masses first appear within the periphery 

 of the chlorophyll-corpuscle, they have the appearance of 

 confluent oily drops, in consistence, outline, and movement, 

 resembling a volatile rather than a fatty oil. And the sub- 

 sequent formation from them of the crystalloidal processes 

 probably results from the conversion, at least in part, of the 

 oily substance into resin. The whole of the exuded mass 

 does not assume the crystalloidal form, but there is always a 

 remnant of the original substance left like a mother liquor, 

 out of which the crystalloidal bodies have solidified. There 

 is, then, here a mixture of substances with which the colour- 

 ing matter of the chlorophyll-corpuscle is in part incorpo- 

 rated, which being insoluble in water, dilute salt solutions, 

 and acids, and completely soluble in alcohol, ether, benzol, 

 bisulphide of carbon, petroleum, volatile oils, &c., must be 

 referred to the group of resins and fats. The colour of the 



