654 
DR. C. A. MAC MUNN ON THE CHROMATOLOGY OF ACTINT2E. 
On treating an alcoholic solution with a little nitric acid the band at D disappeared, 
the solution changed to gamboge-yellow (gaslight), and a band from X535 toX509 was 
seen. The abrupt absorption of the violet end of the spectrum was not removed by 
the acid. 
On treating some alcoholic solutions with caustic potash the colour became redder 
(gaslight) and the band at D was no longer seen, and in a thin layer a band could be 
seen from about A. 548'5 to X 509, but in a deeper layer it extended up to X 458'5. 
On treatment of the latter solutions with ammonium sulphide a faint bluish tinge 
appeared and quickly disappeared, and now some shading at D appeared. 
If an alcoholic solution be treated with ammonia alone a splendid purple-blue 
solution is obtained, giving a dark band from X 660 up to X 516, and another from 
X 498* * * § 5 to X475. The first broad band was strongly shaded at first on the redward 
side, but it eventually changed to that shown in spectrum 12, Chart III. On 
diluting this solution with more alcohol it became a deep blue, and in the more dilute 
solution a band was seen from X 645 to X 548'5 with its darkest part from X 627 to 
X 582. On neutralising this solution with acetic acid it became yellow, and the 
whole of the blue and violet part of the spectrum was now strongly absorbed, and in 
a thin layer the same kind of double band as that of the original alcoholic solution 
was seen. 
The same colouring matter occurs in the tentacles, as I have proved, and they contain 
no hsematin-yielding substance, this being confined to the endodermal parts of the 
body from which I could not extract any of the above-mentioned pigments. I do not 
think, in the present state of knowledge of the Cliromatology of Actiniae, that one is 
justified in calling this pigment by a new name, but so far as my experience goes it is 
peculiar to this species. In its colour-changes with acids it has a very remote 
resemblance to the purple pentacrinin of Professor Moseley,'" also to the colouring 
matter of Aplysia, t but differs in spectrum and in some colour-changes. It has also 
a slight resemblance in character of spectrum and colour-changes to the colouring 
matter obtainable from the petals of some red flowers, e.g., scarlet geranium, red rose, 
&c., but the respective spectra are not the same. 
Out of Cerianthus membranaceus, according to Heider,^; by means of ammoniacaJ 
water, a colouring matter can be extracted which Krukenberg§ calls purpuridin, 
but he says it gives no absorption bands, and as the above pigment does give bands, 
they cannot be the same. 
I failed to find any yellow cells in Sagartia parasitica; its colouring matter 
appears to me to be capable of uniting with oxygen and of giving it up again, and is, 
therefore, probably of respiratory use. 
* Loc. cit. 
t Professor- Moseley, loc. cit., also myself in Proc. Birm. Phil. Soc., vol. iii., 1883, p. 392. 
X Loc. cit. 
§ “ Vergleichend-physiologische Studien,” 2 te Reihe, 3 te Abth., 1882, p. 72. 
