62 Journal of Agricultural Research voi. xxn.No. » 



The average percentage of barren florets of tlie parental varieties was 19. 

 The average percentage of barren florets of the Fj varietal crosses, includ- 

 ing crosses of Little Club with vulgare varieties, was 15. The vulgare- 

 Emmer and Little Club-Emmer crosses produced 75 per cent barren 

 florets, while an average of 70 per cent of barren florets was obtained 

 from the durum-vulgare and durum-Little Club crosses. 



LITERATURE CITED 

 (i) Anderson, T. 



I919. THE IMI'ROVEMENT OF AGRICULTURAL CROPS BY SELECTION AND HYBRID- 

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(2) Arny, a. C, and Garber, R. J. 



I918. VARIATION AND CORRELATION IN WHEAT, WITH SPECIAL REFERENCE TO 



WEIGHT OF SEED PLANTED. In Jour. Agr. Research, v. 14, no. 9, 

 p. 359-392, 8 fig. Literature cited, p. 391-392. 



(3) Babcock, Ernest Brown, and Clausen, Roy Elwood. 



1918. GENETICS in relation TO AGRICULTURE. XX, 675 p., 239 fig., 4 Col. 



pi. New York, London. List of literature cited, p. 622-647. 



(4) Carrier, Lyman. 



I913. THE immediate effect ON YIELD OF CROSSING STRAINS OF CORN. Va. 



Agr. Exp. Sta. Bui. 202, 11 p., 2 fig. 



(5) Collins, G. N. 



1909. A NEW TYPE OP INDIAN CORN PROM CHINA. U. S. Dept. Agr. BuT. Plant 

 Indus. Bui. 161, 30 p., 2 pi. 



(6) and Kempton, J. H. 



I913. EFFECT OF CROSS-POLLINATION ON THE SIZE OF SEED IN MAIZE. In U. S. 



Dept. Agr. Bur. Plant Indus. Circ. 124, p. 9-15. 



(7) East, E. M., and Hayes, H. K. 



I912. HETEROZYGOSIS IN EVOLUTION AND IN PLANT BREEDING. U. S. Dept. 



Agr. Bur. Plant Indus. Bui. 243, 58 p., 8 pi. Literature cited, p. 



49-51- 



(8) and Jones, Donald F. 



1919. INBREEDING AND OUTBREEDING, THEIR GENETIC AND SOCIOLOGICAL 



SIGNIFICANCE. 285 p., 46 fig. (in text and on 13 pi.). Philadelphia, 

 London. Literature cited, p. 266-277. 



(9) Freeman, George F. 



1919. THE HEREDITY OF QUANTITATIVE CHARACTERS IN WHEAT. In GcneticS, 



V. 4, no. I, p. 1-93, 85 tab. (i fold.) Literature cited, p. 93. 



(10) Hayes, H. K., Parker, John H., and Kurtzweil, Carl. 



1920. GENETICS OP RUST RESISTANCE IN CROSSES OP VARIETIES OP TRITICUM 



VULGARE WITH VARIETIES OF T. DURUM AND T. DICOCCUM. In Jotll. 



Agr. Research, v. 19, no. 11, p. 523-542, pi. 97-102. Literature cited, 

 P- 541-542. 



(11) KezER, Alvin, and Boyack, Breeze. 



1918. MENDELIAN INHERITANCE IN WHEAT AND BARLEY CROSSES WITH PROB- 



ABLE ERROR STUDIES ON CLASS PREQUENafiS. Colo. Agr. Exp. Sta. 

 Bul. 249, 139 p., 95 tab., 10 fig., 9 col. pi. 



(12) Lewis, C. I., and Vincent, C. C. 



1919. pollination of the APPLE. Oreg. Agr. Exp. Sta. Bul. 104, 40 p., 



14 pi. (in text). 



