CAROTINOIDS IN IXVKHTI-HltM'IW 167 



incuts seem to have been made for the brittle-stars or sea-urchins 

 with the except. inn of Merejmvskv's /nnneryt hrine-containing species. 

 M: ii -.Munn (1890) reported a yellow lipochroine in the ('rinoid, Ante- 

 don rosacea, but attempts to ascertain the character of old extracts 

 from other species of sea lilies were unsatisfactory, as might be 

 expected. 



The cchinoderms, like the Crustacea, may also contain various lipo- 

 chromogens. Merejowsky (1883) described a red echinastrinc, a green 

 astroviridine, a gray astrogriseine and a violet astroviolettine, each 

 soluble in water and readily going over into "zoonerythrine" like his 

 vclelline, described in a preceding paragraph. He also described a 

 brown ophiurine in species of brittle-stars. Ultra-microscopic and 

 ultra-filtration studies on solutions of these and the crustacean "lipo- 

 chromogens" would throw some light on whether colloidal phenomena 

 are involved, as was suggested above. 



Carotinoids in Molluscs 



One does not ordinarily associate carotinoid-like colors with these 

 animals among which are represented the various species of oysters, 

 mussels, snails and octopus. Merejowsky (1881, 1883), however, has 

 designated a number of species of gastropods (snails) and conchise 

 among the "zoonerythrine" containing animals. It is not stated, how- 

 ever, whether the pigment is in the shells, or in the animals them- 

 selves. More specific is the statement of Krukenberg (1882f) that the 

 liver of the gastropod Helix pomatia sometimes contains a yellow 

 lipochrome showing two absorption bands, one over F and the other 

 between F and G. MacMunn (1883, 1885a) failed to find such a pig- 

 ment in the liver of this species as well as a number of other gas- 

 tropods, finding only "enterochlorophyll," a pigment showing the 

 absorption bands of chlorophyll in the red and green parts of the 

 spectrum, which MacMunn held to be of animal origin. A different 

 result was obtained in the examination of the liver of the mussel 

 Mytilus cdulis, in which a "lutein" pigment, showing an absorption 

 band at F and one between F and G was found in addition to the 

 "enterochlorophyll." In a more recent study of the pigments of mol- 

 lusc livers by Dastre (1899) there is described besides the "chloro- 

 phylloid" (compare with MacMunn's enterochlorophyll) a pigment 

 called cholechrome, which is stated to be intermediate between bili- 

 rubin and lipochrome. Cholechrome, uncontaminated with chloro- 



