VOL. XVn.] PHILOSOPHICAL TRANSACTIONS. 435 



or cornua uteri tempore coitionis, as makes them embrace the ovaria, and such 

 an approach of the uterus and its cornua, as that it may easily transmit the seed 

 into the ovary ; or else that the ova are impregnated by the animalcules after 

 they descend into the uterus, and not in the ovary ; the former seems probable 

 for this reason, that at least a whole cluster of eggs in a hen will be fecundated 

 by one tread of the cock : now this fecundation seems to be in the vitellary, 

 and not in the uterus, as the eggs pass along from day to day, for it can hardly 

 be supposed that the animalcules should subsist so long, being scattered loosely 

 in the uterus, as to wait there for many days for the fecundation of the eggs as 

 they pass along. The latter conjecture has this to strengthen it, that the ani- 

 malcules are found to live a considerable time in the uterus, and that if they 

 should impregnate the ova in the ovary itself, the foetus would increase so fast, 

 that the ova could not pass through the tubae uteri, but would either burst the 

 ovary, or fall down into the abdomen from the orifices of the tubae ; and that 

 from hence proceed those extraordinary conceptions in abdomine extra uterum. 

 But, 4. Mr. Leuwenhoeck, N° J 47 of the Transactions, to weaken the third 

 consideration, about the conceptions being like to an ovum in the womb, pro- 

 poses a parallel between these animalcules and insects, and insinuates that as the 

 latter cast their skins, and appear of another shape, so the other which at first 

 seem like tadpoles, may cast their outer skin, and then be round, and that this 

 may be the occasion of the round figure of the conception in the womb. To 

 this it may be replied, that according to Mr. Leuwenhoeck's own sentiment, 

 the animalcules cannot come forward, if they do not find the punctum or pro- 

 per place for their nourishment, to which it seems they must have some ad- 

 hesion. Now the conception in viviparous animals is not fastened to the womb 

 for many days, nor adheres to any point of it ; so that it seems this roundish 

 body is not the animalcule, thus changed after having cast an outer skin, but is 

 rather the cicatricula, or little egg, into which the animalcule has entered, as 

 its purlctum or place of nourishment : otherwise I do not see why they should 

 not be adhering to the womb from the first conception, or why many hundreds 

 of them are not conceived and formed together. 



The Tramit of the Planet Mercury over the Sun, October 31, 169O, in the 

 Morning, observed at Nuremberg. By Joh. Phil. Wurtzelbaur. N" 192, 

 p. 483. 

 gh 3Qm /pj^g gyj^ emerged out of the clouds ; above his disc, in the field of 

 observation, at the distance of more than half a digit from the ver- 

 tical to the right hand, though really to the left, Mercury appeared 

 quitting the sun's limb. 



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