Colouring-matters of the so-called Bile of Invertebrates, fyc. 371 



intestine of Echinodermata, e.g., in the radial or pyloric coeca of star- 

 fishes. As this colouring-matter is always found in the appendages of 

 the enteron, I propose the name Enter ochloropJiyll for it. Zoochlorophyll 

 would be a shorter and more euphonious name, but as chlorophyll has 

 been found in the integument of several Invertebrates, the same name 

 would apply to the latter, hence the former is more suitable. 



I shall take the animals seriatim, and proceed to describe the 

 results of my examination, prefacing the observations with this 

 remark — that I have relied on the spectroscopic and chemical proofs 

 of the presence of chlorophyll. It is useless to expect that the chloro- 

 phyll in the state in which it occurs should be capable of developing 

 oxygen in the presence of sunlight in the livers of Mollusca or in the 

 pyloric coeca of starfishes, &c, so that one is deprived of the aid of 

 the test which is mainly relied upon by recent observers, such as 

 Professor Lankester* and Mr. P. Geddes;f but fortunately the 

 amount of material obtainable allows one to compare the spectra of 

 enterochlorophyll, in different solutions, with those of chlorophyll 

 obtained from leaves, and to study their respective spectra when the 

 colouring-matters are treated by certain reagents. When this is done, 

 the conclusion forces itself on one's attention that the enterochloro- 

 phyll, obtained from the sources already mentioned, is the same as 

 that which occurs in plants ; for when two colouring-matters have the 

 same spectrum when dissolved in the same medium, and when their 

 respective spectra are altered in the same manner by the same reagent, 

 then we may conclude, according to Vogel and Kundt, that the two 

 colouring-matters are identical. The spectrum of chlorophyll, or 

 rather of the mixture of colouring-matters which compose it, namely, 

 blue chlorophyll, yellow chlorophyll, and chlorofucine is so peculiar J 

 that its presence is easily detected, and its decomposition, or change, 

 by acids gives rise to no less characteristic spectra. I have not deter- 

 mined how much, relatively to each other, of each of these ingre- 

 dients is present in individual cases, but the differences which do occur 

 are no doubt due to the fact that sometimes one, sometimes the other, 

 is present in greater or less amount, and that other pigments, such as 

 lutein or a xanthophyll, may be present.§ Before describing the 

 colouring-matters obtainable from the bile or liver of Invertebrates, I 



* " On the Chlorophyll Corpuscles and Amyloid Deposits, of Spongilla and 

 Hydra," " Quart. Journ. Mic. Sci.," vol. xxii, p. 229. 



f " Proc. Eoy. Soc. Edin.," and " Nature," January 26, 1882. 



% See Dr. Sorby's paper on " Comparative Vegetable Chromatology," " Proc. Eoy. 

 Soc," 1873, vol. 21, pp. 442-483, and bis other papers, a list of some of which is 

 given in last edition (2nd English) of Sachs' " Botany." 



§ In those cases in which the band in red is nearer the violet than usual, it is 

 probably due to the chlorophyll being present in the fluid in a more or less acid 

 state. Cf. Eusseli and Lapraik, " A Spectroscopic Study of Chlorophyll," " Journ. 

 Chem. Soc," 1882, vol. 41, p. 334. 



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