308 Dr. E. Schunck. 



position, some of which, as I have pointed out on former occasions, are 

 very stable bodies, might be looked for in the excrements of animals. 



Having treated some of the faeces of a cow that had been fed for some 

 time on grass only, with boiling alcohol, I obtained a dark greenish- 

 brown extract showing an acid reaction, a quantity of undigested 

 matter consisting of stems, woody fibre, &c., being left undissolved. 

 A little of the filtrate, on being mixed with water and shaken up with 

 ether, gave a golden-yellow supernatant liquid, which, if chlorophyll 

 had been present in the material used, would have shown a decided 

 green colour, and would have exhibited the absorption spectrum of 

 chlorophyll. In place of the latter, however, it showed the four 

 absorption bands of phylloxanthin, as well marked, indeed, as I have 

 ever seen them. This simple experiment proved conclusively the 

 absence of chlorophyll, but in its place the presence of one of its 

 products of decomposition. I have made no attempt to isolate and 

 purify this supposed phylloxanthin, this being rendered difficult owing 

 to the large admixture of impurities, which are chiefly of a fatty nature. 

 The ethereal liquid just referred to would also have contained the 

 urobilin of the fasces ifpresent, so I imagine at least if I have rightly 

 understood what has been stated regarding that body. The pro- 

 perties of urobilin, however, are not very marked. It is only by 

 its absorption spectrum that it can with certainty be detected, but 

 this spectrum is too inconspicuous and too faint to be easily seen in a 

 solution containing at the same time phylloxanthin with its dark well- 

 defined bands, which would completely mask those of urobilin situated 

 as these are in the same region of the spectrum. Its presence, too, if 

 proved, would have been of little interest from my point of view, and 

 I therefore made no attempt to establish its presence or absence. 



The extract of fasces with boiling alcohol gave, after filtration and 

 cooling, a dark-coloured flocculent deposit, which was filtered off, 

 dried, and treated with boiling chloroform. The filtered chloroform ic 

 liquid left on evaporation a quantity of purplish-blue lustrous crystals. 

 These crystals, which are of considerable interest as regards both their 

 properties and their origin, will be described presently. They are 

 more readily prepared by extracting cow-dung after pressure between 

 folds of paper with cold chloroform, filtering, and evaporating the 

 filtrate slowly in a warm place, when the substance separates in the 

 form of brilliant semi-metallic spangles floating in the liquid, which, 

 after collecting and washing with alcohol, have the appearance of a 

 lustrous crystalline mass. From the brilliancy of its appearance an 

 observer might easily be deceived as regards its quantity, which is 

 not really large. I have, however, obtained sufficient to enable me to 

 determine its chief properties, and to justify the conclusion that it is a 

 derivative of chlorophyll closely resembling, though not identical 

 with, phyllocyanin, as I shall presently show. 



