X. EB'FECTS OF DEFICIENCY 379 



that iil)c)flavin particijialos in tat syiitliosis by those oigaiiisins. If tlie 

 fatty materials required wore supplied preformed, the requirement for ribo- 

 flavin niitj;ht well be decreased thereby. 



R. IN PLAN IS 

 U. K. IIORWITT 



Riboflavin is apparently synthesized by higher plant life," ■ '- as evidenced 

 by its distribution in oui' \ogotablo foods. There is no recorded evidence of 

 ril)oflavin deficiency in })lants. 



According to (ialston,''* riboflavin determines the photooxidation of in- 

 doleacetic acid and may be regarded as a photoreceptor in light-growth re- 

 actions. Ferri''' has emphasized the fact that the induction of the photoinac- 

 tivation of indoleacetic acid is a property common to many fluorescent 

 substances. It has been known that the photooxidation of indoleacetic acid 

 could be determined by eosin'^ and that eosin-treated roots yielded less 

 auxin than untreated ones.'" It will be interesting to observe the develop- 

 ment of this subject. 



C. IN INSECTS 



M. K. HORWITT 



It has been apparent for some time'^ that riboflavin is essential for many 

 insects. Among those whose requirements have been studied are the larvae 

 of the flesh fly, Sarcophagia sp.,'^ the cockroach, Blattella germanica,^^ the 

 larvae of the confused flour beetle, Tribolium conjusum,-^--^ Drosophila 

 larvae,-- and the yellow fever mosquito, Aedes aegyptiP 



Fraenkel and Rlewett,^^ who have made extensive studies of the nutri- 

 tional requirements of beetles, have shown that riboflavin is required by 

 Tribolium and Ptinus, but that Lasiodermia, Sitodrepa, and Silvanus do 

 not need riboflavin in their diet because of the presence of intracellular 

 symbiotic microorganisms which synthesize the vitamin. 



" P. R. Burkholder, Science 97, 562 (1943). 



12 J. Bonner, Botan. Gaz. 103, 581 (1942). 



13 A. W. Galston, Science 1H, 619 (1950). 

 "M. G. Ferri, Arch. Biochem. 31, 127 (1951). 



16 F. Skoog, J. Cellular Comp. Physiol. 7, 227 (1935). 



16 P. Boysen-Jensen, Planta 22, 404 (1934). 



1' R. Craig and W. M. Hoskins, Ann. Rev. Biochem. 9, 617 (1940). 



i« G. Di Maria, Arch. zool. ital. 25, 469 (1938). 



IS C. M. McCay, Physiol. Zool. 11, 89 (1938). 



2" G. Frobrich, Z. vergleich. Physiol. 27, 336 (1939). 



21 K. OfThaus, Z. vergleich. Physiol. 27, 384 (1939). 



" E. L. Tatum, Proc. Natl. Acad. Set. U. S. 25, 490 (1939). 



23 W. Trager and Y. SubbaRow, Biol. Bull. 75, 75 (1938). 



2^ G. Fraenkel and M. Blewett, J. Exptl. Biol. 20, 28 (1943). 



