542 PHILOSOPHICAL TRANSACTIONS. [aNNO 1795. 



cannot suppose that the foetus, when it has reached the vagina, can pass out in 

 any other way than through the external parts. That this is really the case, and 

 that in this way it gets into the false belly, is highly probable for the follow- 

 ing reasons. The false belly has muscles to bring its mouth as near as possible 

 to the opening of the vulva, which does not appear necessary for any other pur- 

 pose than that of receiving the foetus. The bones belonging to the mammae and 

 false belly have muscles, which by their action will bring down both these parts 

 towards the vulva, for which no other use can be assigned; and these parts are 

 so much detached from the abdominal muscles, that this effect can be produced 

 during their action to expel the foetus from the uterus. The vulva has naturally 

 an unusual projection, and the margin of the pelvis immediately before it, is 

 rounded and smooth, so as to admit of its moving easily in that direction ; add 

 to this the action of opening the mouth of the false belly, will bring down the 

 skin, and allow the external orifice of the vagina to be thrown still farther out, 

 so as to project more directly over the mouth of the false belly in which the foetus 

 is to be deposited. It is to be observed, that if the parts in their natural state 

 are fitted for such an action, they will be still more so at the period in which it is 

 to be performed ; since in all animals, at that particular time, there are changes 

 going on to facilitate the expulsion of the young in the way most favourable for 

 its preservation. 



The size of the foetus at the time it leaves the uterus, I believe, is not ascer- 

 tained; but it has been found in the false belly attached to the nipple not more 

 than an inch and a quarter in length, and 31 grs. in weight, from a mother 

 weighing 56 lb. In this instance the nipple was so short a way in the mouth that 

 it readily dropped out, we must therefore conclude that it had been very recently 

 attached to it. The foetus at this period had no naval string, nor any remains 

 of there ever having been one; it could not be said to be perfectly formed, but 

 those parts which fit it to lay hold of the nipple were more so than the rest of 

 the body. The mouth was a round hole, just large enough to receive the point 

 of the nipple; the 2 fore-paws, when compared with the rest of the body, were 

 large and strong, the little claws extremely distinct, while the hind legs, which 

 are afterwards to be so very large, were both shorter and smaller than the 

 fore ones.* When the foetus first adheres to the nipple, the face appears to be 

 wanting, except the round hole to receive it; and as the jaws and lips grow, 



♦ Since writing the above, 1 have received from Mr. Lang, in the month of March, 1795, a 

 foetus taken from the false belly, smaller than any that had been met witli. It weighed 21 grs. at 

 the time it was taken from die flilse belly, and was less tlian 1 inch in length. Its fore-paws, while 

 of tliis size, were equally well formed to appearance as in the fcetus above described, and double 

 the length of the hinder ones, but tlie mouth had evidently less widtli. The nipple to which it had 

 been attached did not accompany it. It would seem probable, that the mouth ot the foetus is origi- 

 nally attached to the nipple by means of the gelatinous substance contained in the uterus. — Orig. 



