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It is the pupa, and not the larva, of the Chironomus which has this power; and Grimm further shows that this case, to a certain extent, "unites that of the Cecidomyia with the parthenogenesis of the Coccidae;" the term parthenogenesis implying that the mature females of the Coccidae are capable of producing fertile eggs without the concourse of the male.
The subjects of the alternation of generations, or parthenogenesis, of embryology and biology, owe their great advance, in large degree, to the study of such animals as are parasitic, and the question whether the origin of species be due to creation by the action of secondary laws or not, will be largely met and answered by the study of the varied metamorphoses and modes of growth, the peculiar modification of organs that adapt them to their strange modes of life, and the consequent variation in specific characters so remarkably characteristic of those animals living parasitically upon others.
In a few kinds no males have been found; the females have been isolated after being hatched, and yet have been known to lay eggs, which produced young without the interposition of the males. This parthenogenesis has been noticed in several species. These insects often suddenly appear in vast numbers on various articles of food and about houses, so as to be very annoying. Mr.
Had they been invented, by some inexplicable parthenogenesis in thought, it would indeed have been a marvel had they found application.
But the interdependence of the sexes is so far from being a new fact that it is as old as the evolution of sex, and the decadence and disappearance of parthenogenesis or reproduction from the female sex alone. Once bi-parental reproduction becomes necessary for the continuance of the race, both sexes sink with either, and neither can swim but with both.
We have already dealt with a few faults and shortcomings, evident sometimes and sometimes mysterious, such as the ruinous superabundance and idleness of the males, parthenogenesis, the perils of the nuptial flight, excessive swarming, the absence of pity, and the almost monstrous sacrifice of the individual to society.
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