Observations on certain parts of the animal oeconomy : inclusive of several papers from the Philosophical transactions, etc. / by John Hunter ... ; with notes by Richard Owen.
- John Hunter
- Date:
- 1840
Licence: Public Domain Mark
Credit: Observations on certain parts of the animal oeconomy : inclusive of several papers from the Philosophical transactions, etc. / by John Hunter ... ; with notes by Richard Owen. 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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![the urethra be in that proportion diminished. The semen, in the time of copulation, in such animals as remain long in that ac?' gradually squeezed along the vasa defercntia (as it is secreted; the bulb; and when the testicles cease to secrete, the paroxysm, which is to finish the whole operation, comes on. The semen acting as a stimulus to the cavity of the bulb of the urethra, the muscles of that part of the canal are thrown into action; the fibres neaiest the bladder, probably, act first, and those more forward in quick succession: the semen is projected with some iorce; the blood in the bulb of the urethra is by the same action squeezed forward, but requiring a greater impulse to propel it, is rather later than the semen, on which it presses from behind ; the corpus spongiosum beino- full of blood, acts almost as quick as undulation, in which it is assisted by the corresponding constriction of the urethra, and the semen is hurried along with a considerable velocity.* From the facts which I have stated respecting the organs ot generation, the observations which I have made, and the series of actions which I have considered as taking place in the copulation of animals, I think the following inferences may be fairly drawn. That the bags, called vesiculse seminales, are not seminal reser- voirs, but glands secreting a peculiar mucus; and that the bulb of the urethra is, properly speaking, the receptacle in which the semen is accumulated previous to ejection. Although it seems to have been proved that the vesiculas do not contain the semen, I have not been able to ascertain their particular use ; we may, however, be allowed upon the whole to conclude that they are, together with other parts, subservient to the purposes of generation. 3. ACCOUNT OF THE FREE-MARTIN. Generation, from a seed, requires the concurrence of two causes to give it perfection: the one to form the seed, the other to give it the principle of action.f * [Besides the functions here assigned to the bulb of the urethra, in relation to the reception and propulsion of the semen, wo may also notice its uses in reference to the distention of the glans penis, of which Cowper, in his description of the male organs of the opossum above quoted, gives a remarkable example. He observes : As the bulb of the urethra in man is framed for the use of the glans, to keep it sufficiently distended when required, so it seems it is necessary to have two of these bulbs inclosed with their particular muscles in this animal, to main- tain the turgescence of its double or forked glans when the penis is erected. (Phil Trans., vol. xxiv., 1704, p. 1585.)] f Tt may be necessary for some of my readers to have explained to them what I mean by a seed. I do suppose that the word seed was first applied to grain, or](https://iiif.wellcomecollection.org/image/b21131545_0036.jp2/full/800%2C/0/default.jpg)
