DR. C. A. MAC MUNIS' ON THE CHROMATOLOGT OF ACTINIAE. 
647 
show that the pigment has been altered by extraction with glycerin, but its molecular 
condition may be altered. It is well known that the spectrum of a pigment may 
differ in the solid and liquid state without any necessary change in its composition 
(Vogel and Kundt). 
Bimodes crassicornis .—As already stated, this species has been examined by 
Professor Moseley, : * who found that the parts scraped off from the general body 
wall and tentacles gave no bands, while those from the circumoral disc did give a 
band, nearly coinciding with the less refrangible band of oxy-hgemoglobin ; he also 
found that most of the western species were entirely green, and in about one in ten 
the tips of the gonidial tubercles retained a bright red colouring. In two specimens 
the tentacles were a beautiful rose colour, and this colour was found to be due to 
Actiniochrome, though it was absent from the entire remainder of the body. I have 
found that the colour and spectra of this species differ considerably in different cases. 
In some obtained from Weymouth the specimens were mostly a dull brownish-green, 
mottled irregularly with red, and the base was also mottled with red. In some a 
green layer was present beneath the ectoderm. (The colour of other specimens will 
be referred to further on.) In the ectoderm of these a band, occupying the same 
position as that in Actinia mesembryanthemum, was present in the red parts. The 
tentacles were colourless at the apices, and those parts of the tentacles which had a 
yellowish-red colour gave spectrum 1, Chart II, which belonged to the ectodermal 
layer. No Actiniochrome could be detected. The red parts of the ectoderm gave 
spectrum 2, Chart II. In none of the tentacles of this variety could “yellow cells” 
be detected. On cutting out the red portions of the ectoderm and digesting them 
in rectified spirit and caustic potash a reddish-yellow solution was obtained, giving an 
ill-defined band before D, and absorption of the violet end of the spectrum, spectrum 3, 
Chart II. On adding ammonium sulphide the hsemochromogen bands appeared, the 
solution becoming redder; the first band extended from X 564’5 toX.554'5, and the 
second from X537 to X 524 - 5. An extraction of the tentacles with alcohol was 
without result. 
The colours of other specimens from the same locality were a dirty green in the 
ectoderm which was mottled with light green spots and with a bright red circumoral 
ring, the tentacles being yellowish with a red zone belonging to the ectodermal layer.! 
The red ectoderm and the brown-red endodermal parts gave the same spectrum as 
the former specimens. The ectodermal and endodermal parts, and also the tentacles, 
contained actiniohsematin, as proved by the action of rectified spirit and caustic potash, 
sulphide of ammonium, &c., the same decomposition products having been obtained as 
in former experiments. No Actiniochrome could be detected with certainty. 
* Loc. cit. 
t The spectrum of these tentacles in the yellowish parts is shown in Chart II., spectrum 1. They hacl 
a bluish-white base, a red median zone, and almost colourless points. The red zone, as said supra ., gave 
the same band as the ectoderm, Ac., and yielded hannochromogen. 
4 O 2 
