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Updated: May 25, 2025
Behind this pronouncement of an expert, one might well shelter oneself; but the question under consideration merits a little further treatment. The reproduction of kind, though usually a bi-sexual process, may, however, normally in rare cases be uni-sexual, and this process is known as Parthenogenesis.
We are not likely to have kingdoms to divide, crowns foretold us by weird sisters, a father's death to avenge, or to kill our wives from jealousy; but Lear may teach us to draw the line more clearly between a wise generosity and a loose-handed weakness of giving; Macbeth, how one sin involves another, and forever another, by a fatal parthenogenesis, and that the key which unlocks forbidden doors to our will or passion leaves a stain on the hand, that may not be so dark as blood, but that will not out; Hamlet, that all the noblest gifts of person, temperament, and mind slip like sand through the grasp of an infirm purpose; Othello, that the perpetual silt of some one weakness, the eddies of a suspicious temper depositing their one impalpable layer after another, may build up a shoal on which an heroic life and an otherwise magnanimous nature may bilge and go to pieces.
We may call this reduced number N and the full number 2N. The ova developing by parthenogenesis and giving rise to males segment in the usual way, and all the cells both of soma and gametocytes contain only N chromosomes.
To sum up, judging by the three species that form the subject of my investigations, the Halicti have two generations a year: one in the spring, issuing from the mothers who have lived through the winter after being fecundated in the autumn; the other in the summer, the fruit of parthenogenesis, that is to say, of reproduction by the powers of the mother alone.
The same idea that, before, in parthenogenesis, sacrificed the future of the hive to the unwonted multiplication of males, now sacrifices the male to the future of the hive. This idea is always astounding; and the further we penetrate into it, the fewer do our certitudes become.
There confronts us here the great mystery or precaution of Nature, that is known as parthenogenesis, and is common to a certain number of insects, such as the aphides, the lepidoptera of the Psyche genus, the hymenoptera of the Cynipede family, etc.
The smaller eggs develop without fertilisation, by parthenogenesis, and become males. Here then we have three kinds of gametes, large eggs, small eggs, and sperms, each with the same number of chromosomes. It is not the mere number then which makes the difference, but we find a segregation in the ova into what may for convenience be called female ova and male ova.
Parrots, change of colour in; imitative faculties of; living in triplets; affection of; colours and nidification of the; immature plumage of the; colours of; sexual differences of colour in; musical powers of. Parthenogenesis in the Tenthredinae; in Cynipidae; in Crustacea. Partridge, monogamous; proportion of the sexes in the; Indian; female. Partridge-"dances."
Of the union of the two sexes, females alone are born; parthenogenesis gives birth at the same time to females and males. When the mother, the original genitrix, has been able once to dispense with a coadjutor, why does she need one later? What is the puny idler there for? He was unnecessary. Why does he become necessary now? Shall we ever obtain a satisfactory answer to the question?
It may be here worth noticing that in some cases of parthenogenesis, the embryos within the eggs of silk moths which had not been fertilised, pass through their early stages of development and then perish like the embryos produced by a cross between distinct species.
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