Page:Popular Science Monthly Volume 84.djvu/168

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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; however, one of the seeds in the abnormally colored Mcintosh apple already described contained two embryos, while a second seed of the same character was found in another specimen of this variety. The manner of origin of these accessory 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