Memoir on the reproduction of the opossum, Didelphis virginiana / by Ch.D. Meigs.

  • Meigs, Charles D. (Charles Delucena), 1792-1869.
Date:
[1847]
Catalogue details

Licence: Public Domain Mark

Credit: Memoir on the reproduction of the opossum, Didelphis virginiana / by Ch.D. Meigs. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Memoir on the Reproduction of the Opossum. Didelphis Virgitiiana. By Ch. D. Meigs, M.D. Read March 19, 1847. Notwithstanding Professor Owen has thrown so much light upon the gestation of the marsupiata, by his publication as to that process in the kangaroo, (macropus major,) I hope a few additional observations that I have had an opportunity to make may be considered as an acceptable contribution to that curious point of natural history and physiology. It appears to me that both M. Milne Edwards, in his Elemens de Zoologie, and M. Pou- chet, in his Zoologie Classique, continue under great misapprehensions as to the state of the very early marsupial embryo; if, indeed, it deserves any longer to be considered as an embryo, or even as a foetus: terms which cannot, physiologically speaking, be right- fully applied to a mammiferous quadruped, enjoying in full force all the attributes of a warm-blooded and respiratory existence. M. Milne Edwards, at p. 265 of his volume on the mammiferes, after mentioning the peculiarities of the urethro-sexual canal and wombs, in the marsupials, adds: “Cette dis- position entraine des anomalies extreme dans le mode de reproduction des marsupiaux; les petits ne se developpent pas comme d’ordinaire, dans la poche uterine, mais sont promptement expulses au dehors, et naissent dans un etat d’imperfection telle qu’ on ne peut les comparer qu’ des embryons a peine ebauches. Ce sont des petits corps gela- tineux, informes et incapables de mouvement, dont les divers organes ne sont pas encore distincts, et dont l’existence serait impossible si la nature n’avait assure leur conservation par des moyens particuliers.” M. Pouchet, at p. 262 of the Zoologie Classique, Tome I., says, “ Le produit de la generation qui en arrivant la {the pouch,) n’est qu’ un simple ovule encore baigne de fluides albumineux, se trouve pose sur les tetines Us ne prennent alors de nouriture que par la bouche sans jamais ainsi que P a emis de Blainville, etre en rapport avec la mere au moyen d’un ombilic.” I propose to show that M. Edwards and M. Pouchet are both mistaken in their views as to the state of the marsupial young, and that, instead of being little “ corps gelatineux, informes et incapables de mouvements,” or in the state of a “ simple ovule encore baigne de fluides albumineux,” it is in the full enjoyment of a powerful respiratory, circulating,