APPLE VARIATION 



165 



Double Apples. Section about two thirds natural size. 



that of the polyembryonic seeds already noted, perhaps by a sort of 

 fasciation or doubling of the ovule and the production in it of two 

 distinct egg cells. 



The seeds of the Mcintosh apple appear, indeed, to abound in anoma- 

 lous forms. Another seed in the same abnormally colored apple was 

 remarkable for its small size, being perfectly formed, but of scarcely one 

 fourth the length of an ordinary seed. Other seeds of this variety have 

 been found in which the seed coat failed to develop and the embryo 

 grew to full size without the usual brown covering, traces of which were 

 found as a small patch at the hilum. An instance of this kind has also 

 been noted in a seed of the Ehode Island Greening. In other cases the 

 seed coats have split open as the seed developed, apparently as the 

 result of the excessive production of endosperm which protruded as an 

 irregular whitish mass containing the embryo. Though it is possible 

 that such forms are the result of some unnatural state of nutrition in 

 the seeds of this variety, nothing is known of the conditions which give 

 rise to their production. Owing to the comparatively infrequent occur- 

 rence of abnormal forms, an investigation of their underlying causes is 

 more difficult than the study of normal variation and progress is con- 

 sequently slower. 



