170 CAROTINOIDS AND RELATED PIGMENTS 



as in the sponges Hircinia spinosula, Suberites flavus, Tedania Mug- 

 giana and Suberites massa, while in others, namely, Papillina suberea 

 and Tcthya Lyncureum, xanthophyll is indicated. The ether extract 

 of the soap, after the petroleum ether treatment, in most cases showed 

 only a single absorption band, from which Krukenberg drew the 

 conclusion as to the presence of a rhodophane-like pigment. Pig- 

 ment of this character is apparently not present in all sponges. For 

 example, Krukenberg found only carotinoid-like pigments in Suberites 

 flavus and Pipillina suberea. Other sponges which contain pigment 

 showing two-banded spectra, according to Krukenberg, are Reniera 

 aquaeductus, Cocospongia, Chondrosia renijormis, Aplysina aero- 

 phoba, and Suberites domuncula. 



MacMunn (1888) reported spectroscopic studies of the lipochromes 

 of a number of additional species of Porifera, which throw still further 

 light on the widespread occurrence of carotinoid-like pigments in the 

 sponges. His method was to examine the alcoholic extracts of the 

 sponges for absorption bands and then shake the alcoholic solution 

 with CS 2 and repeat his observations on the CS 2 solutions. Neither 

 solution would be expected to show the character of the carotinoids 

 present inasmuch as alcohol extracts both classes of pigments from 

 tissue, and also since xanthophylls are partly epiphasic between 

 alcohol and carbon disulfide. However, if chromolipoid pigments 

 remained in the alcohol after the carbon disulfide extraction, this fact 

 would indicate the presence of xanthophylls. 



Almost all of MacMunn's observations of absorption bands of the 

 lipochromes in both alcohol and carbon disulfide show the carotinoid 

 nature of the lipochromes. In general they favor carotin rather than 

 one of the xanthophylls. In three species, namely, Halma Bucklandi, 

 Halichondria albescens and Leuconia Gossei, one lipochrome was 

 found showing only a single absorption band. The species Halichon- 

 dria incrustans and Halichondria seriata may contain both carotin 

 and xanthophylls since the alcohol remaining after the carbon disul- 

 fide extraction still showed carotinoid absorption bands. On the 

 other hand, carotin alone may be the chromolipoid in the species 

 Halichondria caruncula and Halichondria rosea, whose alcohol ex- 

 tracts were left practically colorless by the carbon disulfide. No 

 information of a similar nature is given for the species Halichondria 

 panicea, Hymeniacidon albescens, Grantia coriacea, Halichondria san- 

 guinea and Pachymatisma Johnstonia, comprising the remaining 

 species examined. 



