126 PHILOSOPHICAL TRANSACTIONS. [ANNO 1797. 



full effects of impregnation, and in the other no traces of it would be seen ; instead 

 of which, the procreative actions are no further advanced where there has been an 

 opportunity for the passage of the semen, than in those cases where the passage has 

 been impossible. But if we defer the mutilation till the ovary has perfected its 

 work, which it does in a rabbit in something more than 50 hours from the ap- 

 proach of the male, then the generative process is not disturbed, and the evolution 

 of the foetus goes on in the usual manner ; for now all the different parts of the 

 uterine system being in a condition to act, each performs its peculiar office. 



1st. The semen by its presence stimulates either the vagina, os uteri, cavity of 

 the uterus, or all of them. — 2d. The impression made on these is propagated to the 

 ovaries by consent of parts. — 3d. One or more of the ovarian vesicles enlarges, pro- 

 jects, bursts, and discharges its contents. — 4th. During this process in the ovary, 

 the tube is undergoing a state of preparation for the purpose of embracing the ovary, 

 and receiving the rudiments of the foetus. — 5th. This preparation consists in part 

 of an increased turgescence of its vessels, and a consequent enlargement of its fim- 

 briated extremity. When thus prepared, it approaches the ovary. — 6th. After the 

 tube has performed its office by a peristaltic motion, commencing at the fimbriae, 

 and terminating in the uterus, it gradually returns to its former situation and con- 

 dition. — 7th. While these different actions are going on in the appendages of the 

 uterus, others not less important to the design of nature are instituted in the uterus 

 itself : for the tunica decidua, where it is obvious, it is formed ready to secure firmness 

 of connexion between the tender ovum and internal surface of the uterus, till a pro- 

 per attachment by means of placenta can be effected. — 8th. By way of guarding 

 with additional security against a premature escape of the ovum, an apparatus, 

 seated in the neck and mouth of the womb, now begins to develope its real struc- 

 ture, and perform its proper action, consisting in the secretion of a mucus-like sub- 

 stance, sufficient in quantity to fill completely the whole length of the neck, and 

 by that means to seal up the communication between the cavity of the uterus and 

 vagina. — 9th. Nor does the care of nature for the preservation of the new animal 

 terminate here ; for while she is by various means forming and perfecting her work, 

 at least as far as comes within the province of the uterine system, she is at the same 

 time making preparation for its nourishment after birth, by instituting the proper 

 secretion of the breasts. 



When we take a reflected survey of these successive operations, I think it must 

 appear, on tracing nature's steps through the different stages of this work, that 

 they are the product of that law in the constitution which is called sympathy, or 

 consent of parts. That the semen first stimulates the vagina, os uteri, cavity of 

 the uterus, or all of them. By sympathy the ovarian vesicles enlarge, project, and 

 burst. By sympathy the tubes incline to the ovaries, and having embraced them, 

 convey the rudiments of the foetus into the uterus. By sympathy the uterus makes 

 the necessary preparation for perfecting the formation and growth of the foetus. 

 And, by sympathy the breasts furnish milk for its support after birth. Having now 



