FUNGI AS TEST ORGANISMS 225 



RoBBiNS, W. J.: Effect of extracts of Phycomyces upon its development, Am. Jour. 



Botany 27: 559-564, 1940. 

 Roberts, E. C, and E. E. Snell: An improved medium for microbiological assays 



with Lactobacillus casei, Jour. Biol. Chem. 163 : 499-509, 1946. 

 RoGOSA, M.: Microbiological method for the quantitative determination of small 



quantities of potassium, Jour. Biol. Chem. 154: 307-308, 1944. 

 *Ryan, F. J. : The germination of conidia from biochemical mutants of Neurospora, 



Am. Jour. Botany 35: 497-503, 1948. 

 Ryan, F. J., and E. Brand: A method for the determination of leucine in protein 



hydrolysates and in foodstuffs by the use of a Neurospora mutant, Jour. Biol. 



Chem. 154: 161-175, 1944. 

 ScHOPFER, W. H.: Etude d'un cas de stimulation unilaterale et d'un cas d'inhibition 



chez un micro-organisme, Compt. rend. soc. phys. hist. nat. Genhve. 50: 152-154, 



1933. 

 ScHOPFER, W, H.: Recherches sur I'emploi possible d'un test vegetal pour la vitamine 



Bi. Essai d'etalonnage. Bull. soc. chim. biol. 17: 1097-1109, 1935. 

 ScHOPFER, W. H. : Les Tests microbiologiques pour la determination des vitamines, 



Experientia 1 : 1-68, 1945. 

 ScHOPFER, W. H., and M. Guilloud: Un cas de stimulation unilateral chez las 



microorganismes explique par une action vitaminique, Verhandl. naturforsch. 



Ges. Basel 61: 299-314, 1945. 

 ScHULTZ, A. S., L. Atkin, and C. N. Frey: Determination of vitamin Bi by yeast 



fermentation method. Improvements related to the use of sulfite cleavage and 



a new fermentometer, Ind. Eng. Chem., Anal. Ed. 14: 35-39, 1942. 

 Shankman, S.: Amino acid nutrition of Lactobacillus arabinosus, Jour. Biol. Chem. 



150:305-310, 1943. 

 Smit, J., and E. G. Mulder: Magnesium deficiency as the cause of injury in cereals, 



Mededeelingen van de Landbouwhoogeschool, Deel 46, Verhandeling 3, 1942. 

 Snell, E. E. : The microbiological assay of amino acids. Advances in Protein Chem. 2 : 



85-118, 1945. 

 Snell, E. E. : The vitamin Be group. Evidence for the occurrence of pyridoxamine 



and pyridoxal in natural products, Jour. Biol. Chem. 157: 491-505, 1945a. 

 *Snell, E. E.: Use of microorganisms for assay of vitamins, Physiol. Revs. 28: 255- 



282, 1948. 

 Srb, a. M., and N. H. Horowitz: The ornithine cycle in Neurospora and its genetic 



control, Jour. Biol. Chem. 154: 129-139, 1944. 

 Tatum, E. L., M. G. Ritchey, E. V. Cowdry, and L. F. Wicks: Vitamin content of 



mouse epidermis during methylcholanthrene carcinogenesis. I. Biotin, choline, 



inositol, p-aminobenzoic acid and pyridoxine, Jour. Biol. Chem. 163 : 675-682, 



1946. 

 Vandeca\teye, S. C. : Biological methods of determining nutrients in soil in Diagnos- 

 tic Techniques for Soils and Crops (edited by H. B. Kitchen), The American 



Potash Institute, Washington, 1948. 

 * White, W. L., R. T. Darby, G. M. Stechert, and K. Sanderson: Assay of cellu- 



lolytic activity of molds isolated from fabrics and related items exposed in the 



tropics, Mycologia 40 : 34-84, 1948. 

 Wright, L. D., E. L. Cresson, H. R. Skeggs, T. R. Wood, R. L. Peck, D. E. Wolf, 



and K. Folkers: Biocytin, a naturally-occuring complex of biotin. Jour. Am. 



Chem. Soc. 72: 1048, 1950. 

 Wyss, O., V. G. Lilly, and L. H. Leonian: The effect of pH on the availability of 



p-aminobenzoic acid to Neurospora crassa, Science 99: 18-19, 1944. 



