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But passing over this difficulty, and supposing a male and female Dog to be produced at the same time from the Hyaena stock, the progeny of the pair, if the analogy of the simpler kinds of Agamogenesis* is to be followed, should be a litter, not of puppies, but of young Hyenas.
In favour of this hypothesis, Professor Kölliker adduces the well-known facts of Agamogenesis, or "alternate generation;" the extreme dissimilarity of the males and females of many animals; and of the males, females, and neuters of those insects which live in colonies: and he defines its relations to the Darwinian theory as follows:
It is obvious, from these extracts, that Professor Kolliker's hypothesis is based upon the supposed existence of a close analogy between the phenomena of Agamogenesis and the production of new species from pre-existing ones. But is the analogy a real one? We think that it is not, and, by the hypothesis, cannot be. For what are the phenomena of Agamogenesis, stated generally?
But the chances of early colonization are in favour of species which, multiplying by agamogenesis, can people a whole shore from a single germ; and against species which, multiplying only by gamogenesis, must be introduced in considerable numbers that some may propagate.
But passing over this difficulty, and supposing a male and female Dog to be produced at the same time from the Hyæna stock, the progeny of the pair, if the analogy of the simpler kinds of Agamogenesis is to be followed, should be a litter, not of puppies, but of young Hyænas.
Let us suppose Hyaenas to have preceded Dogs, and to have produced the latter in this way. Then the Hyena will represent A, and the Dog, B. The first difficulty that presents itself is that the Hyena must be asexual, or the process will be wholly without analogy in the world of Agamogenesis.
In favour of this hypothesis, Professor Koelliker adduces the well-known facts of Agamogenesis, or "alternate generation"; the extreme dissimilarity of the males and females of many animals; and of the males, females, and neuters of those insects which live in colonies: and he defines its relations to the Darwinian theory as follows:
The production of new species, or genera, is the extreme permanent divergence from the primitive stock. All known Agamogenetic processes, on the other hand, end in a complete return to the primitive stock. How then is the production of new species to be rendered intelligible by the analogy of Agamogenesis?
It is obvious, from, these extracts, that Professor Koelliker's hypothesis is based upon the supposed existence of a close analogy between the phaenomena of Agamogenesis and the production of new species from pre-existing ones. But is the analogy a real one? We think that it is not, and, by the hypothesis cannot be. For what are the phaenomena of Agamogenesis, stated generally?
No case of Agamogenesis is known in which, when A differs widely from B, it is itself capable of sexual propagation. No case whatever is known in which the progeny of B, by sexual generation, is other than a reproduction of A. But if this be a true statement of the nature of the process of Agamogenesis, how can it enable us to comprehend the production of new species from already existing ones?
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