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In the bats and lemurs the "horns" are very short, and the lower common part is longer. Finally, in the apes and in man the blending of the two halves is complete, and there is only the one simple, pear-shaped uterine pouch, into which the oviducts open on each side. This simple uterus is a late evolutionary product, and is found ONLY in the ape and man. Origin of human ova in the female ovary.
Thus we have these two little sacs of living substance, each growing in a similar manner, one to the inside of an ovary, the other to the inside of an anther. Naturally, it is the living substance in these little sacs that is important.
The stigmas themselves are of a different shape, more flattened and not cylindrical. The pollen falls from the anthers abundantly on them, and germinates in the ordinary manner. The ovary which in lamarckiana and in all other new forms is wholly underneath the calyx-tube, is here only partially so. This tube is inserted at some distance under its summit.
If it be true that the number of eggs is limited, and that there are not more than from 15 to 20 in each ovary, it is evident that sterility must ensue when these 15 or 20 eggs have been detached without fecundation.
Patrick Blair, for instance, claimed that "honey absorbed the pollen," and thus fertilized the ovary. Pontidera thought that its office was to keep the ovary in a moist condition. Another botanist argued that it was "useless material thrown off in process of growth."
And when a pollen grain lands on a pistil and joins with the ovule prepared in the ovary, the two components are united again. Out of the now complete seed a new and complete plant can arise. Goethe understood that he would be taught a correct conception of this process only by the plant itself.
In proof of the fact that the special features of the mammals have been inherited by man, I will, in conclusion, point out the identical way in which the ova are formed in the ovary. There again, as in the whole of his morphology, man proves indubitably his descent from the mammals.
O'Donoghue, however, concludes from a study of the Marsupial Dasyurus that the stimulus which upon the milk glands proceeds from the corpora lutea in the ovary. In this animal changes in the pouch occur in pregnancy, which are doubtless also due to hormone stimulation, but which we will not consider here. Journ. Mic.
There are first the essential organs of generation, differing in the two sexes, the ovary furnishing the egg, the testes furnishing the seed or sperm; then the organs of sexual contact; the secondary sex characteristics, such as stature, distribution of hair, deposits of fat, shape of body and especially of the pelvis, the voice, smoothness of skin, muscular development, etc.
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