392 



Dr. C. A. MacMunn. 



reagent developed a band in red between C and D, and another cover- 

 ing D, exactly as figured in the above-mentioned chart of spectra. The 

 centre of the first was at X634, of the second at X589. In an alcoholic 

 solution of artificially prepared hydrobilirubin caustic soda develops 

 the same bands, but in an alcoholic solution of febrile urobilin they are 

 not seen after it is added, a band in green being seen instead. 



I have isolated febrile urobilin several times, and find its spectra 

 coincide with those previously described,* and that the two bands near 

 D are as much part of the spectrum as that at F. So-called indigo- 

 blue gives a band before D, and " omicholin " one after D, but I find 

 that these bands give totally different readings, and neither was 

 present in the isolated pigment ; but this will be again referred to. 



The Colouring -matters of Sheep and Ox Bile. — When some brown- 

 green sbeep bile in a thickness of 18 millims. was placed before the 

 slit of the spectroscope (one-prism, chemical), the spectrum was 

 absorbed at one end at \744 completely, at the other at X534 ; the 

 shading was continued for some slight distance over the visible spec- 

 trum ; between these points three bands were visible, viz. : — 



1st Band X666— 634 



2nd „ X610— 587*5 



3rd „ X576— 561 



In the same depth of brown ox bile three bands are also visible 

 which had the same position. f Absolute alcohol was now added to 

 both specimens of bile, and they were then filtered. 



The ox bile filtrate appeared to have a slightly red fluorescence ; it 

 had a red colour (by gaslight it was dichroic, vide infra), and gave 

 four bands as follows : — ■ 



1st Band 

 2nd „ 

 3rd „ 

 4th „ 



\656— 643. Centre, 

 X612— 584 -5. 

 X578-564. „ , 



X536— 518. 



648 -5 

 596 

 570 

 528 



When this was shaken with chloroform, the latter took up the 

 colouring-matter and was dichroic ; looked down upon in a beaker, it 

 appeared red, but had a greenish tinge with transmitted daylight. 

 This gave a spectrum of four bands : — 



1st Band X651— 634 



2nd „ X604— 581 -5 



3rd „ X571 -5—561 



4th „ X534--516 



* " Proc. Roy. Soc," 1880, vol. 31, p. 26. 



f Maps of the spectra of ox and sheep bile are given in the paper published in 

 " Proc. Roy. Soc." already referred to. 



