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re afterwards advanced to the more powerful sex. For proof of this, the economy of bees is cited; when they wish to raise a queen-bee, or true female, they prepare for the larva a more commodious cell, and feed it with delicate food. But we shall here stop to remark on the author's argument up to this point. It is manifest, according to his hypothesis, that neither sex nor species depend on the ancestral germ, but simply on physical conditions and mechanical development. But eminent physiologists deny that the facts are such as he has stated; they deny, as we have stated in a former section, that the foetal progress is such as the _Vestiges_ represent them to be; they deny that the human embryo, for example, exhibits in successive stages the form of fish, lizard, bird, beast: on the contrary, they contend that it is only in the earliest period of the organic germ, when the manifestations are almost too obscure for microscopic sense, that any resemblance exists; that immediately the organic germ becomes sensible to observation, sex and species are found to be fixed. Take, for example, the vertebrata; in these, by some mysterious bond of union, the organic globules are seen to arrange themselves into two nearly parallel rows. We may then say that the keel of the animal is laid down, and in it we have the first rudiments of a backbone and a continuous spinal chord. But during the progress and completion of this first organic process no changes have been observed assimilating the nascent embryo to any of the inferior animals. The next series of changes in the germinal membrane are of two kinds--in one the nervous system, the organs of motion, the intestinal canal, the heart and blood-vessels are manifested; the other set of changes, which are subsequent, produce the perfection of the animal and determine its sex. All these manifestations result from germinal appendages that cannot be severed or changed without ruin to the embryo, and the conditions essential to life as the structure advances are due temperature, due nutriment of the nervous organs, and due access to the atmospheric air. Without, therefore, pursuing further this part of the inquiry, we shall remark that the question at issue between the _Vestiges_ and its opponents is one of facts--of conflicting evidence--to be tried by the jury of the public, or rather by those who, from science or professional pursuits, are competent to form an authoritative opinion. Our
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