Colouring-matters of the so-called Bile of Invertebrates, fyc. 381 



An ether solution was pale yellow and showed two bands, the 

 first from \498— 480, the second from \466— 450. 



A bisulphide of carbon extract of an orange colour gave two bands, 

 the first from \530— 507, the second from \496— 476 (?) Petroleum 

 also extracted a little colouring-matter, giving a band from A 505 — 

 484. Hence the principal colouring-matter present evidently 

 belonged to the class of luteins, of which I believe there are more 

 than one. 



Carcinus mamas : Liver and Bile. — Several specimens of this 

 Crustacean were examined. The bile itself, in most cases, only gave 

 an ill-defined band, between green and blue. The presence of entero- 

 chlorophyll was found to be exceptional, and that of lutein or a lutein 

 pigment constant. The colour of the liver in different specimens 

 varies remarkably, thus in sorne it was yellowish-white, in others, 

 orange, orange-yellow, &c. It became almost black on exposure 

 to the air. In all of the specimens alcohol, ether, chloroform, and 

 bisulphide of carbon extracted the colouring-matter, giving bands in 

 the blue end of the spectrum, which seemed to be due to lutein as 

 already stated, and I believe a similar pigment occurs in the coloured 

 membrane lining the shell, while in some cases tetronerythrin was 

 also present. 



In some alcohol solutions two enterochlorophyll bands were visible, 

 the first from X670 — 651, the second from X612 — 592 ; with a little 

 nitric acid the colour became slightly greenish. In most cases a 

 band was visible in the same solution froni\X505 — 484. 



Ether solutions showed the presence of two well-marked bands, 

 the first from \498— 480, the second X463— 448. A bisulphide 

 solution was orange- red, and gave two bands ; the first from X530 — 

 507, the second from U96— 476. 



Pagurus bemhardits. — The brown-yellow bile of three specimens 

 gave the band of enterochlorophyll in red, and- a shading including 

 b and F. The pale-yellow alcohol extract gave the same bands. The 

 solution was too dilute to give a satisfactory result with nitric acid. 

 (Sp. 12.) 



Astacus fluviatilis. — While none of the above Crustaceans showed 

 the slightest evidence of the presence of hsematin in their bile, or in 

 the alcoholic extracts of their livers, the crayfish contains it in con- 

 siderable amount. So far as I know this has not been discovered 

 before. The brownish-yellow liquid which exudes from the liver 

 gave a faint band between D and E, and a dark one between b and F, 

 measuring X515 — 488, and on adding sulphide of ammonium two 

 bands appeared which are those of reduced heematin. In the bile of 

 some specimens examined the first reduced hsematin band appeared 

 without any treatment whatever ; both were strongly intensified by 

 caustic soda, as was found to be the case in the Pulmonate Mollusca. 



