1894.] 



NATURAL SCIENCES OF PHIL,ADEJLPHIA. 



53 



CONTRIBUTIONS TO THE LIFE-HISTORIES OF PLANTS, No. X. 



By THOMAS MEEHAN. 



THE Origin of Coreless Apples. 



There are apple trees whicli have occasionally apetalous flowers 

 and bear fruit which is, as popularly stated, coreless. The pre- 

 cise morphology of this condition has never been explained. Re- 

 cently some specimens were presented to the Academy by Mr. 

 Anchutz of Arch Street, Philadelphia, from a tree growing on the 

 grounds of Captain F. J. Williams, in PleasantsCo., West Virginia. 

 Though bearing fruit abundantly every year it never had lieen 

 known to have a "blossom," that is to say, petals. The corrugated 

 appearance of the apex of the apple suggested the course of 

 growth which results in the "navel" varieties of orange, explained 

 in Proceedings of the Academy, July 25, 189o, p. 292, 

 and an examination showed that a similar explanation applies 

 to the apple as well as the orange. The ordinary apple is 

 simply an arrested branch in which the leaves, with the axis, 

 have been transformed into the succulent or carpellary structures 



FiK. 1. 



Fig 2. 



which go to make up the fruit. But in these coreless apples, the 

 growth- wave resulting in the production of fruit did not become so 

 fully arrested, but made a renewed though weaker rhythm. This 

 was sufficient to draw nutrition from the original fruiting wave, and 

 perhaps interfere with its proper pollination, thus permitting the 

 formation of an upper carpellary system, — weak, certainly, but 

 sufficiently well situated to secure pollen and produce a few 



