212 PHYSIOLOGY OF THE INVERTEERATA. 



In 1884, Krukenberg stated that cyanein occurs in Velella, 

 Aurelia, Cyanea, and Bhizostoma. 



Dr. MacMunn* has examined the pigments from the 

 following ActinicB : — Actinia mesembryanthetnum, Bunodes 

 crassicornis, B. hallii, Sagartia hellis, S. dianthus, S. para- 

 sitica, S. viduata, S. troglodytes, and Antheci cereus. 



(a) When the solid portions from the ectoderm, endoderm, 

 and tentacles of the red-coloured specimens oi Actinia mesem- 

 iryanthemv/m were examined by the microspectroscope, they 

 gave a band which closely resembled that of reduced hasmo- 

 globin, accompanied by two other bands nearer the violet 

 end of the spectrum. The extreme edges of the shading of 

 the band extend from X 600 to A 560, while its darkest part 

 is from X 580 to X 563. " These measurements vary accord- 

 ing to the colour of the specimen, for in brown specimens 

 the dominant band is nearer the violet, and in some a band 

 is also present before D." The latter spectrum is said to 

 belong to modifications of the same pigment, as the same 

 decomposition products are obtained in both cases. The 

 spectrum of the brown specimens of this species has a close 

 resemblance to the histohsematins. MacMunn has named 

 this pigment actiniohseraatin. 



ActiniohEematin is soluble in glycerol, but it is insoluble in 

 alcohol, ether, chloroform, carbon disulphide, benzene, &c. 

 This pigment is also extracted (but in a changed condition) 

 by treating with alcohol and potassium hydroxide (either hot 

 or cold). By the latter treatment a reddish solution is 

 always obtained, which gives a band at D, generally extending 

 from X 625 to X 589, recalling to mind the spectrum of 

 alkaline hsematin. When ammonium sulphide was added to 

 the alkaline alcoholic extract, the band at D was replaced by 

 two bands which are undistinguishable from the spectrum of 

 hsemochromogen. MacMunn has also observed that all the 

 red pigments in the Actinia; gave after this treatment in the 



* Philosophical Transactions of Boyal Society, 1885 (part ii.), p. 641 ; and 

 Quarterly Journal of Microscopical Science, vol. 30. 



