An inaugural dissertation on organogeny : submitted to the dean and faculty of the Medical College of the State of South-Carolina for the degree of M.D., and recommended by the medical committee for publication / by Myddelton Michel.

  • Michel, Middleton, 1822-1894.
Date:
1846
Catalogue details

Licence: Public Domain Mark

Credit: An inaugural dissertation on organogeny : submitted to the dean and faculty of the Medical College of the State of South-Carolina for the degree of M.D., and recommended by the medical committee for publication / by Myddelton Michel. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    success which had rewarded his assiduous researches. The cor- puscule, encountered two years previously by Prevost and Du- mas, was now shown to be identical with the ovum found in the tubes. But here the truth was not, as we might have sup- posed, irrevocably consigned to the annals of science in all its perspicuity; the strange interpretation which it suffered in his hands, consecrated an error that masked the principles it unfold- ed; divided the laurels which its discoverer alone should have gathered, and bore that complicated abstruseness which revealed the metaphysical doctrines of the school to which it belonged, while, it was divested of that pleasing simplicity and rational analogy it should always wear. Baer, unable to disengage himself from an idea so prevalent that the graafian vesicles were the ova, only saw in this dis- covery a confirmation of the belief; and at once endeavored to establish the analogy which was supposed to exist between them and the ova of ovipara. In this erroneous comparison, the tu- nics of the graafian vesicle were likened to the protective envel- opes of the bird's egg; the fluid contents represented the vitellus; the granular layer, and what we term the cumulus granulosus, {tunica granulosa of Barry,) were the granular membrane and discus proligerus]—while, according to this view, the ovum itself, situated within the disk, was supposed to be analogous to the germinal vesicle in birds. But this survey ruffled the knowl- edge entertained of the function of the constituent parts of the bird's egg, which was so well known; for while in the one the germinal vesicle resolved itself into the formation of the cicatri- cula,—in the other it was eliminated, and in itself realized the evolution of all subsequent development; in the one the vitel- lus was incorporated, and essential to the ovum,—in the other it was external to it, and inservient to no purpose. These contra- dictions were either lost sight of, or were reconciled by an effort of imagination, which, however we may admire its ingenuity, we must condemn its extravagance. In presence of the high rank man holds in the scale of ani- mated creation, Baer perhaps conceived the possibility of a sim- ilar superiority ab initio; and in the unrecognised ovum, its characteristics forcing themselves upon consideration, though only as an element of the graafian vesicle, itself supposed to be the ovum, by a singular interpretation of facts, he regarded the condition to be that of an uegg within an egg, or uan ovum, raised to the second power as he termed it, and carrying out the equation, (if I be allowed this expression,) the formula of the corollary was: as the egg is in the egg, so is the animal within the animal, or the foetal within the parent organism. This was another signal illustration of the ready conversion of results to the subserviency of entertained views, and of the in-