. A text-book of comparative physiology for students and practitioners of comparative (veterinary) medicine . ng in the middle; 5, ligament of ovary; o, intact horn ofuterus; ,, a born thrown open; 8, body of uterus, upper face; !), broad ligament;10, cervix, with its mucous folds; 11, cul-de-sac of vagina with its folds of mucousmembrane; 13, urinary meatus and its valve, 14; 15, mucous fold, a vestige of hy-men; 10, interior of vulva; 17, clitoris; 18,18, labia of vulva; 19, inferior commis-sure of vulva. THE DEVELOPMENT OF THE EMBRYO ITSELF. 133 Semen itself, though composed essentially of
. A text-book of comparative physiology for students and practitioners of comparative (veterinary) medicine . ng in the middle; 5, ligament of ovary; o, intact horn ofuterus; ,, a born thrown open; 8, body of uterus, upper face; !), broad ligament;10, cervix, with its mucous folds; 11, cul-de-sac of vagina with its folds of mucousmembrane; 13, urinary meatus and its valve, 14; 15, mucous fold, a vestige of hy-men; 10, interior of vulva; 17, clitoris; 18,18, labia of vulva; 19, inferior commis-sure of vulva. THE DEVELOPMENT OF THE EMBRYO ITSELF. 133 Semen itself, though composed essentially of spermatozoa,is mixed with the secretions of the vas deferens, of the seminalvesicles, of Cowpers glands, and of the prostate. Chemically itis neutral or alkaline in reaction, highly albuminous, and con-tains nuclein, lecithin, cholesterin, fats, and salts. The movements of the male cell, owing to the action of thetail (cilium), suffice of themselves to convey them to the ovi-ducts ; but there is little doubt that during or after sexual con-gress there is in the female, even in the human subject, at least. Fig. 138 —Uterus and ovaries of the sow. semi-diagrammatic (after Dalton). 0, ovary;II, Fallopian tube; h, horn of the uterus; 5, body of the uterus; v, vagina. in many cases, a retrograde peristalsis of the uterus and ovi-ducts which would tend to overcome the results of the activityof the ciliated cells lining the oviduct. It is known that themale cell can survive in the female organs of generation forseveral days, a fact not difficult to understand, from the methodof nutrition of the female cell (ovum) ; for we may suppose thatboth elements are not a little alike, as they are both slightlymodified amoeboid organisms. Nervous Mechanism —Incidental reference has been made tothe directing influence of the nervous system over the eventsof reproduction; especially their subordination one to anotherto bring about the general result. These may now be consid-ered in greater det
Size: 2148px × 1163px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookpublishernewyo, bookyear1890
