Reproduction 379 



Xenia. Examine ears of corn from plots in which a starchy 

 dent variety has been grown alongside of, or together with, a sweet 

 corn. In the case where sweet corn was planted note particu- 

 larly the influence of the starchy variety in modifying endosperm 

 characters, and compare this with the amount of modification in 

 the other variety. 



Parthenocarpy.- - Examine the seedless fruits of any material 

 available, such as banana, grape, navel orange. Determine 

 the extent of ovular development. If English forcing cucumbers 

 (such as the Telegraph) are available, cut out the stamens before 

 the pollen is matured, bag the flower, and determine the effect 

 upon the development of fruit in comparison with that of a fruit 

 hand-pollinated at the proper time. 



REFERENCES 



CHURCH, A. H. Types of Floral Mechanism. 1:211 pp., 39 



pis., 1908. 

 CORRENS, C. Bastarde zwischen Maisrassen, mit bes. Beriick- 



sichtigung der Xenien. Bibl. Bot. Orig.-Abh. a. d. Gesammt- 



gebiet d. Bot. 53 : 161 pp., 2 pis., 1901. 

 COULTER, J. M., and CHAMBERLAIN, C. J. Morphology of 



Angiosperms. 348 pp., 1903. 



DARWIN, CHARLES. Cross and Self-fertilization in the Vege- 

 table Kingdom. 469 pp., 1885. [Appleton.] 

 EWERT, R. Die Parthenocarpie oder Jungfernfruchtigkeit der 



Obstbaume. 57 pp., 18 figs., 1907. 

 FLETCHER, S. W. Pollination in Orchards. Cornell Agl. Exp. 



Sta. Bui. 181 : 335-364, figs. 65-86, 1900. 

 KLEBS, G. Willkiirliche Entwickelungsanderungen bei Pflanzen. 



166 pp., 28 figs., 1903. 



- Uber Variationen der Bliiten. Jahrb. f . wiss. Bot. 42 : 155- 



320, 27 figs., 1 pi., 1905. 

 LEWIS, C. I., and VINCENT, C. C. Pollination of the Apple. 



Oregon Agl. Exp. Sta. Bui. 104 : 40 pp., 14 pis., 1909. 

 LIDFORSS, B. Weitere Beitrage zur Biologie des Pollens. Jahrb. 



f. wiss. Bot. 32 : 232-312, 1899. 



