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THE POPULAR SCIENCE MONTHLY 



Double Apples. About two thirds natural size. 



the apples last described the receptacles of the blossoms must have been 

 united nearly to the base of the sepals. In the first specimen, however, 

 union appears to have taken place only at the base. 



Polyembryony, or the multiplication of the embryos in the seed, is 

 a condition normal in certain cases, notably in the citrus fruits and the 

 Mango. Such seeds arise from ovules containing a single egg cell which 

 gives rise to one of the embryos ; the others originate as outgrowths, by 

 a sort of budding process, from the inner wall of the embryo sack and 

 of course reproduce the parent form as perfectly as other methods of 

 bud propagation. True polyembryony must not be confused with the 

 presence of more than one seed in an indehiscent fruit which normally 

 contains a single seed. Such an occurrence is quite common in the 

 peach and related fruits where the stone is really the endocarp or inner 

 portion of the fruit and may enclose two seeds produced independently 

 of each other, though the normal number is but one. 



The carpels of the apple may contain from one to four seeds each, 

 though the most common number appears to be two. I am not aware 

 that a polyembryonic apple seed has been reported up to this time ; how- 

 ever, one of the seeds in the abnormally colored Mcintosh apple already 

 described contained two embryos, while a second seed of the same char- 

 acter was found in another specimen of this variety. The manner of 

 origin of these accessor}' embryos was not determined, though each 

 embryo appeared to be surrounded by an independent inner seed coat. 

 This fact would seem to indicate a method of production different from 



