CAROTIN, THE PRINCIPAL YELLOW PIGMENT OF MILK FAT. 327 



the yellow constituent of chlorophyll or Hansen's "Chlorophyll Yellow." 

 He believed that the lipochromes were chemically closely related to 

 chlorophyll. 1 



MacMunn's greatest contribution to animal chromotology was in 

 iSSg. 2 The pigments of a great many marine animals, Crustacea, 

 worms and sponges were examined and classified. Lipochromes were 

 found abundantly, MacMunn drawing a distinction as to whether the 

 lipochrome was a rhodophan or a chlorophan-like lipochrome. 



In regard to some of the properties of the lipochromes MacMunn 

 states, as did Krukenberg, that they are sensitive to light, both in the 

 solid state and in solution, and yield in many cases cholesterin-like 

 substances. He believed that many of the plant lipochromes were 

 identical with the animal lipochromes. 



It will be remembered that for a long time there were many 

 followers of the view that a close relationship existed between carotin 

 and cholesterol and that this view was only finally discredited by a 

 study of the pure crystalline pigment. 



Cotte 3 recently carried out an investigation in which he sought 

 and claims to have shown that the lipochromes, both animal and 

 vegetable are intimately associated with cholesterol. Cotte's results 

 have been thoroughly disproved by Henze. 4 



Since the early work of Pouchet 5 and Maly 6 who distinguished 

 between yellow and red crustacean lipochromes many investigators 

 have classified the lipochromes according to their red or yellow color, 

 Newbigin 7 in a recent investigation of the pigments of the skin, 

 muscle and ovaries of the salmon, reports that he found two pigments 

 present, a red and a yellow, which he claims he was able to separate 

 from each other. Newbigin concluded from the color reactions of 

 the pigments that the red pigment was a true lipochrome while the 

 yellow pigment was not. 



In regard to the yellow pigment, Newbigin says that, "It belongs 

 to a group of pigments that are apparently exceedingly widely dis- 

 tributed in the animal kingdom, but which have been little investigated. 

 They have been commonly confounded with the lipochrome pigments." 



He extracted the pigment from the bright yellow body fat of a 

 cow and found it to have properties identical with the yellow pigment 



1. Jour. Physiol. 9, p. 1 (1888). 



2. Quart Jour. Micros. Sc. 30, p. 15 (1889). 



3. Compt. Rend. Soc. Biol. 55, p. 812 (1903). 



4. Zeit. Physiol. Chem. 41, p. 109 (1904). 



5. Jour. d. 1'Anat. de la Physiol. 1, 12, 10 (1876). 



6. Sitz. d. k. Akad. d. Wiss. zu. Wein. 83 (1831). 



7. D. Noel Patton Report of Inv. on Life Hist, of Salmon ( 1898 ) , Article XT. 



