Whether the male is formed more quickly than the female.
Whether on the fortieth day the fetus is of the same size as a large ant.
Further one inquires whether the male is formed more quickly than the female.
1. And it seems not. For to the extent something is more perfect, then with just so much more difficulty does it acquire its perfection. But the male is more perfect than the female. Therefore, etc.
2. In addition, moisture is easily bounded by something else. But the female is moister than the male. Therefore, she is more quickly bounded when she is in the uterus.
3. Moreover, "if the one born is a female, her purgation will occur over thirty days, but if a male, over forty days."
The Philosopher says the opposite. For he says that the male moves after forty days, and the female does not move before ninety days.
Further, one inquires whether on the fortieth day the fetus is of the same size as a large ant.
And it seems not, because after conception an amount of the menses and sperm exceeding the size of an ant is enclosed in the womb. Therefore, the one generated in the womb is larger than this.
The Philosopher says the opposite.
To the first question one must reply that configuration arises quickly from the strength of the heat, and the heat is stronger in the male, and this is why he is shaped more quickly in the uterus. Therefore, the Philosopher says that if what is retained in the womb falls on the fortieth day into cold water, the thing will appear to be wrapped in a web about the size of a large ant, at least if it is a male. If it is a female, however, then it does not appear formed yet on the fortieth day and this is owing to nothing other than its weak heat. Nevertheless, one must understand that there is a good bit of diversity with respect to pregnancy. When the fetus is formed over a given period of time, it will move in double that time and it will be born in triple that time. And this is why wise physicians say that movement doubles the time from conception, but birth triples it.
In the same way there is another difference, because in the first six days the conceived semen becomes almost like milk, and then over nine days it is changed into blood, and after that, over twelve days, it is consolidated, and then over nine days it is given shape, and the time after that prepares it for birth. But at least according to the Philosopher's understanding, the male is formed more quickly than the female in the natural course of things. If the opposite should occur, it will be contrary to nature.
1. On to the arguments. To the first, one must reply that the more perfect a thing is, the more slowly it attains its ultimate perfection; nevertheless, it can attain another perfection more quickly.
2. To the second argument one must reply that there is something that is moist and fluid, and a thing like this is given shape quickly and then quickly loses it, just as water immediately receives the impression of a seal and immediately loses it. But there is something that is at the same time both moist and solid, and something like this is not so easily given shape.
Or one can say differently that although the semen is shaped according to the womb, nevertheless the shape of the animal cannot be quickly formed. Thus the moist is poorly bounded by its own boundary, and this is why the seed of the female, which is more moist, acquires its bounded state more slowly.
3. To the third argument one must reply that the Philosopher says that if the one born is female, purgation will occur after thirty days. But it is different for its formation. This is why the argument does not prevail.
To the other thing asked, one must reply that the proportion of a child outside the uterus to one inside the uterus is the same as that of a fully-grown man to a child. Therefore, in the first month it has, as it were, its smallest size and later acquires a size similar to that of a kind of worm since, although the composite or the semen may have a large size, the whole of it is not converted into the fetus's substance. Some is converted into the fetus's substance, and some is reserved for nourishing it, and some is expelled just like the feces and a superfluity.
With this a solution to the argument is apparent.
-  "Worm": vermis, elsewhere for A. a more generic term and thus might be translated "insect."