250 REPRODUCTION 



5. Prepare ovules of the flowers from which the anthers are 

 taken, beginning with the youngest stages. Several ovules may 

 be removed together from the ovary by cutting out a thin strip 

 of the placenta to which they are attached. Prepared in this 

 way they are much easier to orient as desired on the microtome 

 than where a single ovule is handled by itself. Hunt for the 

 stages shown in Fig. 131, and make drawings. 



6. Treat as above ovules taken at different periods after polli- 

 nation, and make drawings to show processes of fertilization. 



7. In connection with the laboratory work read from the 

 following books. Morphology of Angiosperms, by Coulter and 

 Chamberlain. D. Appleton & Co., N. Y. Fecundation in 

 Plants, by D. M. Mottier. Carnegie Institution, Washington, 

 D. C. Mendel's Principles of Heredity, by W. Bateson. G. P. 

 Putnam's Sons, N. Y. Die Stofflichen Grundlagen der Verer- 

 bung, by Eduard Strasburger. Gustav Fischer, Jena. Vorlesun- 

 gen iiber Descendenztheorien, by J. P. Lotsy. Gustav Fischer, 

 Jena. Proceedings American Breeders' Association, Vols. IV 

 and V, Washington, D. C. Plant Breeding, by L. H. Bailey. 

 The Macmillan Co., N. Y. Plant Breeding, by Hugo de Vries. 

 The Open Court Pubhshing Co., Chicago. 



