EXPERIMENTAL EMBRYOLOGY 407 



Hamner, C. L., Schomer, H. A., and Marth, P. C. 1944. Application of growth- 

 regulating substance in aerosol form with special reference to fruit-set in 

 tomato. Bot. Gaz. 106: 108-123. 



Hannig, E. 1904. Uber die Kultur von Cruciferen Embryonen ausserhalb des 

 Embryosacks. Bot. Ztg. 62: 45-80. 



Hedemann, E. 1931. tlber experimentelle Erzeugung von Adventivembryonen 

 bei Mirabilis uniflora und Mirabilis frdebelii. Biol. Zentbl. 51: 647-652. 



Holman, R. M., and Brubaker, F. 1926. On the longevity of pollen. Calif. 

 Univ. Pub. Bot. 13: 179-204. 



Howlett, F. S. 1943. Growth promoting chemicals improve greenhouse tomato 

 production. Ohio Agr. Expt. Sta. Bimo. Bui. 28: 17-27. 



. 1944. Comparative value of growth regulating chemicals for greenhouse 



tomato production. Proc. Ohio Veg. & Potato Growers Assoc. 29th Ann. 

 meeting 29: 162-180. 



. 1946. Synthetic plant hormones in relation to greenhouse tomato pro- 

 duction. Ohio Veg. and Potato Growers Rep. 1946, pp. 223-236. 

 -, Freeman, S., and Marth, P. C. 1946. Aerosol applications of growth 



regulating substances to greenhouse tomato. Proc. Amer. Soc. Hort. Sci. 48: 



485-474. 

 Ivanov, M. A. 1938. Experimental production of haploids in Nicotiana rustica 



L. Genetica 20: 295-397. 

 Jones, M. D., and Newell, L. C. 1948. Longevity of pollen and stigmas of 



grasses: Buffalograss, Buchloe dactyloides (Nutt.)Engelm., and Corn, Zea mays 



L. Jour. Amer. Soc. Agron. 40: 195-204. 

 JOrgensen, C. A. 1928. The experimental production of heteroploid plants in 



the genus Solarium. Jour. Genet. 19: 133-211. 

 Katayama, Y. 1932. Crossing experiments in certain cereals with special refer- 

 ence to different compatibility between the reciprocal crosses. Mem. Col. 



Agr. Kyoto Univ. 27 (Genetic Ser. 2) : 1-75. 

 . 1934. Haploid formation by X-rays in Triticum monococcum. Cyto- 



logia 5: 235-237. 



1935. Karyogenetic studies on X-rayed sex cells and their derivatives 



in Triticum monococcum. Agr. Col. Jour. Tokyo Imp. Univ. 13: 333-362. 

 Kent, N., and Brink, R. A. 1947. Growth in vitro of immature Hordeum em- 

 bryos. Science 106: 547-548. 

 Kihara, H. 1940. [Formation of haploids by means of delayed pollination in 



Triticum monococcum.] Bot. Mag. [Tokyo] 54: 178-185. 

 and Katayama, Y. 1932. [On the progeny of haploid plants of Triticum 



monococcum.] Kwagau 2: 408-410. 

 and Yamashita, K. 1938. Kiinstliche Erzeugung haploides und triplo- 



ides Einkornweizen durch Bestaubung mit rontgenbestrahlten Pollen. Comra. 



Papers, 30th Anniv. N. Akemine, pp. 9-20. 

 Kostoff, D. 1941. The problem of haploidy (cytogenetic studies on Nicotiana 



haploids and their bearings to some other cytogenetic problems). Bibl. 



Genetica 13: 1-148. 

 Laibach, F. 1925. Das Taubwerden der Bastardsamen und die kiinstliche 



Aufzucht fruh absterbender Bastardembryonen. Ztschr. f. Bot. 17: 417-459. 



