REQUIREMENTS OF INSECTS 



12. F. W. Tanner, S. E. Pfeiffer and J. M. van Lanen, ibid., 29. 



13. M. Landy and D. M. Dicken, /. Lab. Clin. Med., 1942, 27, 1086. 



14. E. E. Snell, Proc. Soc. Exp. Biol. Med., 1944, 55, 36. 



15. E. E. Snell, /. Biol. Chem., 1945, 158, 497. 



16. E. E. Snell and B. M. Guirard, Proc. Nat. Acad. Sci., 1943, 29, 66. 



17. W. Shiva and G. W. Shive, /. Amer. Chem. Soc, 1946, 68, 117. 

 17a. J. T. Holden, C. Furman and E. E. Snell, /. Biol. Chem., 1949, 



178, 789 ; J. T. Holden and E. E. Snell, ibid., 799. 



18. N. Bohonos, B. L. Hutchings and W. H. Peterson, /. Bad., 1942, 



44, 479. 



19. E. F. MoUer, Z. physiol. Chem., 1939, 260, 246. 



20. E. F. Moller, Angew. Chem., 1940, 53, 204. 



21. R. E. Feeney, J. H. Mueller and P. A. Miller, /. Bad., 1943, 46, 



563. 



22. H. Mcllwain, Nature, 1946, 158, 898. 



23. G. W. Kidder and V. C. Dewey, Arch. Biochem., 1949, 21, 58. 



17. EFFECT OF PYRIDOXINE ON fflGHER PLANTS 



Little attention appears to have been paid to the role of pyridoxine 

 in the economy of plants, and the only reported observation of this 

 type is that pyridoxine and a few of its derivatives stimulated the 

 growth of excised tomato roots. ^ 



It has been shown that the amounts of pyridoxine, like that of 

 several other members of the vitamin B complex, increased during the 

 germination of oats, wheat, barley and maize. ^ The distribution of 

 pyridoxine in tomato plants was similar to that of aneurine, ribo- 

 flavine and pantothenic acid ; a concentration gradient was found to 

 exist from the apex of the plant to the base, with the highest concen- 

 trations in the young leaves and tops of the stems. ^ 



Pyridoxine is present in soil and natural manures.* 



References to Sedion 17 



1. W. J. Robbins, Amer. J. Bat., 1942, 29, 241. 



2. P. R. Burkholder, Science, 1943, 97, 562. 



3. J. Bonner and R. Dorland, Arch. Biochem., 1943, 2, 451. 



4. M. A. Roulet, Experientia, 1948, 4, 149. 



18. PYRIDOXINE REQUIREMENTS OF INSECTS 



Pyridoxine is an essential vitamin for several insects, including 

 Drosophila melanogaster ,^ the mosquito Aedes aegypti,^-^ the beetles, 

 Tenebrio molitor,^ Tribolium confusum,^ and Ptinus tedus ^ and the 

 moth Ephestia elutella.^ The beetles, Sitodrepa panicea, Lasioderma 

 serricorne and Silvanus surinamensis, on the other hand, grew well on 



341 



