254 CAROTENOIDS CONTAINING CARBONYL GROUPS XII 



Org. 3 (1893) 26. — M. Newbigin, /. Anat. u. Physiol. 21 (1897) 237. — G. Vegezzi, 

 Dissertation, Fribourg, 1916. — J. Verne, Compt. rend. Soc. Biol. Paris 83 (1920) 963; 

 g4 (1926) 1349; 97 (1927) 1290; Arch. Morph. 16 (1923) i. — E. Chatton, A. Lwoff 

 and M. Parat, Compt. rend. Soc. Biol. Paris 94 (1926) 567. — E. Lonnberg and H. 

 Hellstrom, Ark. Zool. A. 26 (1932) No. 7, etc. 



26. R. KuHN and E. Lederer, Ber. 66 (1933) 4^8. 



27. P. Karrer and co-workers, Helv. chim. Acta ij (1934) 4^2, 745; 18 (1935) 96; ig 

 (1936) 479. 



28. R. KuHN and N. A. Sorensen, Z. angew. Chem. 51 (1938) 465; Ber. 71 (1938) 1879. 



29. R. KuHN J. Stene and N. A. Sorensen, Ber. 72 (1939) 1688. 



30. J. TiscHER, Z. physiol. Chem. 267 (1941) 281. 



31. R. KuHN and E. Lederer, Ber. 66 (1933) 488. 



32. R. KuHN, J. Stene and N. A. Sorensen, Ber. 72 (1939) 1688. — J. Tischer, Z. 

 physiol. Chem. 267 (1941) 281. — Cf. p. 232. 



33. R. KuHN, J. Stene and N. A. Sorensen, Ber. 72 (1939) 1688. — J. Tischer, Z. 

 physiol. Chem. 239 (1936) 257. 



34. J. Tischer, Z. physiol. Chem. 250 (1937) 147; 252 (1938) 225. 



35. R. KuHN, J. Stene and N. A. Sorensen, Ber. 72 (1939) 1688. 



36. J. Tischer, Z. physiol. Chem. 267 (1941) 281. 



36a. M. Hartmann, F. Graf Meden, R. Kuhn and H. J. Bielig, Z. Naturforsch. 2b 



(1947) 330- 



37. R. Kuhn and N. A. Sorensen, Ber. 71 (1938) 1879. 



38. P. Karrer and co-workers, Helv. chim. Acta 17 (1934) 412, 745; ig (1936) 479. — 

 W. Jaffe, Dissertation, Ziirich, 1939. 



39. P. Karrer and co-workers, Helv. chim. Acta 17 (1934) 4^2; 17 (1934) 745; 18 (1935) 

 96, 19 (1936) 479- 



40. H. Willstaedt, Svensk Kem. Tidskr. 46 (1934) 205. 



41. P. Karrer, L. Loewe and H. Hubner, Helv. chim. Acta 18 (1935) 96. 



42. R. Kuhn and N. A. Sorensen, Z. angew. Chem. 51 (1938) 465; Ber. 71 (1938) 1879. 



43. Literature references are given by R. Kuhn and N. A. Sorensen, Ber. 71 (1938) 1882. 



44. R. W. G. Wyckoff, Science 86 (1937) 311. 



45. R. Kuhn and N. A. Sorensen, Z. angew. Chem. 51 (1938) 465. 



46. K. G. Stern and K. Salomon, J. biol. Chem. 122 (1938) 461. 



47. P. Karrer and F. Benz, Helv. Chim. Acta 17 (1934) 412. 



48. R. Kuhn, J. Stene and N. A. Sorensen, Ber. 72 (1939) 1688. In the recent literature, 

 the value 228° is always given. 



49. R. Kuhn, E. Lederer and A. Deutsch, Z. physiol. Chem. 220 (1933) 231. 



50. P. Karrer and L. Loewe, Helv. chim. Acta 17 (1934) 745- 



51. Cf. R. Kuhn and co-workers, Ber. 72 (1939) 1688. 



52. R. Kuhn ,E. Lederer and A. Deutsch, Z. physiol. Chem. 220 (1933) 231. — Cf. P. 

 Karrer and L. Loewe, Helv. chim. Acta 17 (1934) 745. 



53. R. Kuhn and N. A. Sorensen, Ber. 71 (1938) 1879. 



54. Cf. Ber. 71 (1938) 1886. 



55. R. Kuhn and N. A. Sorensen, Ber. 71 (1938) 1887. 



56. R. Kuhn and N. A. Sorensen, Ber. 71 (1938) 1888. 



57. R. Kuhn, J. Stene and N. A. Sorensen, Ber. 72 (1939) 1701. 



58. R. Kuhn and N. A. Sorensen, Ber. 72 (1939) 1699. 



59. H. Braconnot, Ann. Chim. 6 (1817) 122, 133. 



60. J. L. Thudichum, Proc. Roy. Soc. (London) 17 (1869) 253. 



61. T. Pabst, Arch. Pharm. 230 (1892) 108. 



62. F. G. Kohl, Untersuchungen tiber das Carotin mid seine physiologische Bedeutung in 

 Pfianzen, Leipzig 1902. 



63. A. Tschirch, Ber. bot. Ges. 22 (1904) 414. — B. M. Duggar, Washington, Univ. Stud, i 

 (1913) 22. — N. A. Monteverde and C. N. Lubimenko, Bull. Acad. Sci Petrograd. 

 Ser. 6, 7. II (1913) 1105- 



