BLACK: INFLORESCENCE AND FRUIT OF PYRUS MALUS 543 



6. The time of bud differentiation and flower formation in New 

 Hampshire is somewhat variable. The primordia of the flowers 

 may or may not be established at the end of the growing season. 



7. The inflorescence in the apple is a simple cyme, consisting of 

 usually four to seven pedicelled flowers upon a very short peduncle. 



8. The parts of the flower develop in succession from the torus. 

 The greater growth of the cells in the periphery of the torus 

 results in a cup-shaped structure, thus elevating the sepals, petals, 

 and stamens above the epigynous carpels. The apex of the 

 axis is not completely used up in the production of the flower 

 parts. 



9. The inferior ovaries in the apple are embedded in the torus, 

 which grows with the carpels. The mesocarp and exocarp of the 

 carpel become fleshy, whereas the endocarp becomes cartilaginous 

 or papery. 



10. The torus is the receptacle of the flower and by excessive 

 growth produces the flesh of the fruit, in which a well-defined pith 

 and cortical layer can be seen. 



11. Ten primary vascular bundles demark the cortex and pith 

 regions in the apple. The carpellary vascular system arises from 

 these strands. 



12. The fruit of the apple may be considered a reenforced or 

 composite fruit consisting of one to several drupe-like fruits 

 embedded in a fleshy torus and is called a pome. 



For valuable help and criticism, the writer wishes to express 

 her sincere appreciation to Dr. O. R. Butler, who suggested this 

 study, and whose constant advice and assistance made the photo- 

 micrographs possible. 



Literature 



1. Mottier, D. M. Beitrage zur Kenntniss der Kerntheilung in den 



Pollen-Mutterzellen einiger Dikotylen und Monocotylen. Jahrb. 

 Wiss. Bot. 30: 169-204. 1897. 



2. Eneroth, O. Handbok I, Svensk Pomologi, 172-180. 1864. 



3. Forney, E. La taille des arbres fruitiers. 1:21-23. 1907. 



4. Gray, A. Structural botany, i: 40, 144, 214. 1879 [ed. 6]. 



5. Sandsten, E. P. Conditions which affect the time of the annual 



flowering of fruit trees, Wisconsin Exp. Sta. Bull. 137: 1-7. 

 1906. 



6. Kraus, E. J. Gross morphology of the apple. Oregon Agr. Coll. 



Exp. Sta. Res. Bull. no. i, part i. 1913. 



