i66 CAROTENOID HYDROCARBONS OF KNOWN CONSTITUTION X 



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22. B. M. DuGGAR, Washington Univ. Stud, i (1913) 22. 



23. e.g. K, H. Coward, Biochem. J . ly (1923) 134. 



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154- 



25. R. KuHN and C. Grundmann, Ber. 65 (1932) 1880. 



26. G. Mackinney, /. Am. Chem. Soc. 56 (1934) 4^8. 



27. C. MoNTANARi, Chem. Centr. igo5, I, 544. 



28. P. Karrer and R. Widmer, Helv. chim. Acta 11 (1928) 751. 



29. H. Brockmann, Z. physiol. Chem. 216 (1933) 47. 



30. L. Zechmeister and P. Tuzson, Ber. 63 (1930) 1882. 



31. R. Willstatter and H. H. Escher, Z. physiol. Chem. 64 (1910) 52. 



32. R. Willstatter and H. H. Escher, Z. physiol. Chem. 64 (1910) 52. 



33. B. V. EuLER, H. V. EuLER and P. Karrer, Helv. chim. Acta 12 (1929) 279. — H. v. 

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 Ber. 65 (1932) 638. — B. v. Euler and P. Karrer, Helv. chim. Acta 15 (1932) 496. — 

 H. V. Euler, P. Karrer, E. Klussmann and R. More, Helv. chim. Acta 15 

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34. A. Winterstein, Z. physiol. Chem. 215 (1933) 52. 



35. A. Winterstein, and G. Stein, Z. physiol. Chem. 220 (1933) 250. 



36. S. J. B. Connell, Biochem. J. 18 (1924) 1127. 



37. R. Kuhn and H. Brockmann, Z. physiol. Chem. 206 (1932) 45. 



38. P. Karrer and R. Widmer, Helv. chim. Acta 11 (1928) 751. 



39. P. Karrer, A. Helfenstein and R. Widmer, Helv. chim. Acta 11 (1928) 1201. 



40. P. Karrer and co-workers, Helv. chim. Acta 14 (1931) 436. 



41. P. Karrer and J. Rutschmann, Helv. chim. Acta 28 (1945) 793. 



42. R. Kuhn and C. Grundmann, Ber. 65 (1932) 900. 



43. R. Kuhn and C. Grundmann, Ber. 65 (1932) 1887. 



44. P. Karrer and W. Jaffe, Helv. chim. Acta 22 (1939) 69. 



45. R. Kuhn and C. Grundmann, Ber. 65 (1932) 1882 (cf. P. Karrer and W. Jaff6, 

 Helv. 22 (1939) 69. 



46. R. Kuhn and C. Grundmann, Ber. 65 (1932) 1888. 



47. P. Karrer and W. Jaffe, Helv. chim. Acta 22 (1939) 69. 



48. L. Zechmeister and P. Tuzson, Nature 141 (1938) 249; Biochem. J. 32 (1938) 1305; 

 Ber. 72 (1939) 1340- 



49. P. Karrer and H. Kramer, Helv. chim. Acta 2j (1944) 1301. 



50. P. Karrer and A. Helfenstein, Helv. chim. Acta 14 (1931) 78. 



51. L. Zechmeister and co-workers, Proc. Nat. Acad. Sci. 27 (1941) 468. 



52. L. Zechmeister and co-workers. Science 94 (1941) 609. 



53. L. Zechmeister and co-workers, /. biol. Chem. 144 (1942) 315. 



54. L. Zechmeister and co-workers, /. biol. Chem. 144 (1942) 321. 



55. L. Zechmeister and co-workers. Arch. Biochem. i (1943) 231. 



56. A. L. LE RosEN and L. Zechmeister, /. Am. Chem. Soc. 64 (1942 )io75. 



57. L. Zechmeister and J. H. Pinckard, /. Am. Chem. Soc. 6g (1947) 1930. 



58. Zeise, Ann. 62 (1947) 380; /. prakt. Chem. 40 (1847) 297. 



59. A. Arnaud, Compt. rend. 102 (1886) 11 19. 



60. R. Willstatter and W. Mieg, Ann. 355 (1907) I. 



61. L. Zechmeister, L. v. Cholnoky and V. Vrabely, Ber. 61 (1928) 566; Ber. 66 (1933) 

 123. 



62. P. Karrer and co-workers, Helv. chim. Acta 12 (1929) 1142; 13 (1930) 1084; 14 (1931) 

 1033- 



63. R. Kuhn and H. Brockmann, Ber. 65 (1932) 894; 66 (1933) 1319; 67 (1934) 1408; 

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64. cf. Strain, /. biol. Chem. iii (1935) ^5 for the occurrence of carotene in green leaves. 



