§3.2#3πυρούμενον δὲ καὶ ὀπτώμενον οὐ γίνεται σκληρὸν διὰ τὸ εἶναι τὴν φύσιν γεῶδες οὕτως ὥσπερ κηρός· καὶ διὰ τοῦτο θερμαινόμενα μᾶλλον, ἐὰν ᾖ μὴ ἐξ ὑγροῦ περιττώματος, διοροῦται καὶ γίνεται οὔρια.
But when heated or roasted, it does not become hard, because its nature is earthy like wax; and for this reason, when heated, unless it is from a moist residue, it separates and becomes a wind-egg.
τὸ δὲ λευκὸν ὑπὸ μὲν τῶν πάγων οὐ πήγνυται, ἀλλ’ ὑγραίνεται μᾶλλον (τὸ δ’ αἴτιον εἴρηται πρότερον), πυρούμενον δὲ γίνεται στερεόν· διὸ καὶ πεττόμενον περὶ τὴν γένεσιν τῶν ζῴων παχύνεται.
The white, on the other hand, is not solidified by frosts, but rather becomes liquid (the cause of this has been stated before), but when heated by fire it becomes solid; wherefore also when concocted during the generation of the animals it thickens.
ἐκ τούτου γὰρ συνίσταται τὸ ζῷον, τὸ δ’ ὠχρὸν τροφὴ γίνεται, καὶ τοῖς ἀεὶ συνισταμένοις τῶν μορίων ἐντεῦθεν ἡ αὔξησις.
For from this the animal is formed, and the yolk becomes nourishment, and from this the growth of the parts as they are formed is always derived.
διὸ καὶ διώρισται τό τε ὠχρὸν καὶ τὸ λευκὸν χωρὶς ὑμέσιν ὡς ἔχοντα τὴν φύσιν ἑτέραν.
Wherefore also the yolk and the white are separated by membranes, as having different natures.
δι’ ἀκριβείας μὲν οὖν, ὃν τρόπον ἔχουσι ταῦτα πρὸς ἄλληλα κατ’ ἀρχάς τε τῆς γενέσεως καὶ συνισταμένων τῶν ζῴων, ἔτι δὲ περί τε ὑμένων καὶ ὀμφαλῶν, ἐκ τῶν ἐν ταῖς ἱστορίαις γεγραμμένων δεῖ θεωρεῖν· πρὸς δὲ τὴν παροῦσαν σκέψιν ἱκανὸν φανερὸν εἶναι τοσοῦτον, ὅτι συστάσης πρώτης τῆς καρδίας, καὶ τῆς μεγάλης φλεβὸς ἀπὸ ταύτης ἀφορισθείσης, δύο ὀμφαλοὶ ἀπὸ τῆς φλεβὸς τείνουσιν, ὁ μὲν εἰς τὸν ὑμένα τὸν περιέχοντα τὸ ὠχρόν, ὁ δ’ ἕτερος εἰς τὸν ὑμένα τὸν χοροειδῆ, ὃς κύκλῳ περιέχει τὸ ζῷον· ἔστι δ’ οὗτος περὶ τὸν ὑμένα τὸν τοῦ ὀστράκου.
Now, the precise manner in which these stand to one another both at the beginning of generation and as the animals are being formed, and furthermore concerning the membranes and the umbilical cords, must be observed from what is written in the Researches on Animals; but for the present inquiry it is enough that this much should be clear: that when the heart is first formed, and the great vessel has been marked off from it, two umbilical cords extend from the vessel, one to the membrane surrounding the yolk, and the other to the chorioid membrane which surrounds the animal in a circle; and this latter is around the membrane of the shell.
διὰ μὲν οὖν θατέρου λαμβάνει τὴν ἐκ τοῦ ὠχροῦ τροφήν, τὸ δ’ ὠχρὸν γίνεται πλέον· ὑγρότερον γὰρ γίνεται θερμαινόμενον.
Through one of these, then, it receives nourishment from the yolk, and the yolk becomes greater; for it becomes more liquid when heated.
δεῖ γὰρ τὴν τροφὴν σωματώδη οὖσαν ὑγρὰν εἶναι καθάπερ τοῖς φυτοῖς, ζῇ δὲ τὸ πρῶτον καὶ τὰ ἐν τοῖς ᾠοῖς γιγνόμενα καὶ τὰ ἐν τοῖς ζῴοις φυτοῦ βίον· τῷ πεφυκέναι γὰρ ἔκ τινος λαμβάνει τὴν πρώτην αὔξησιν καὶ τροφήν.
For the nourishment, being corporeal, must be liquid, just as in plants, and both those that are formed in eggs and those in animals live at first the life of a plant; for they are naturally constituted to receive their first growth and nourishment from something.
ὁ δ’ ἕτερος ὀμφαλὸς τείνει εἰς τὸ περιέχον χόριον.
The other umbilical cord extends to the surrounding chorion.
δεῖ γὰρ ὑπολαβεῖν τὰ ᾠοτοκούμενα τῶν ζῴων πρὸς μὲν τὸ ᾠχρὸν οὕτως ἔχειν τὸν νεοττὸν ὥσπερ πρὸς τὴν μητέρα τὰ ζῳοτοκούμενα ἔμβρυα, ὅταν ἐν τῇ μητρὶ ᾖ (ἐπεὶ γὰρ οὐκ ἐκτρέφονταί γε ἐν τῇ μητρὶ τὰ ᾠοτοκούμενα, ἐκλαμβάνει τι μέρος αὐτῆς), πρὸς δὲ τὸν ἐξωτάτω ὑμένα τὸν αἱματώδη ὡς πρὸς τὴν ὑστέραν.
For we must assume that the oviparous animals stand in the same relation to the yolk as the viviparous embryos do to the mother when they are in the mother (since the oviparous are not nurtured in the mother, they receive a certain part of her), and to the outermost bloody membrane as to the uterus.
ἅμα δὲ περί τε τὸ ὠχρὸν καὶ τὸ χόριον τὸ ἀνάλογον τῇ ὑστέρᾳ τὸ ὄστρακον τοῦ ᾠοῦ περιπέφυκεν, ὥσπερ ἂν εἴ τις περιθείη περί τε τὸ ἔμβρυον αὐτὸ καὶ περὶ τὴν μητέρα ὅλην.
And at the same time, around both the yolk and the chorion (which is analogous to the uterus) the shell of the egg is grown, just as if someone were to place a covering around the embryo itself and the whole mother.
ἔχει δ’ οὕτως, διότι δεῖ τὸ ἔμβρυον ἐν τῇ ὑστέρᾳ εἶναι καὶ πρὸς τῇ μητρί.
This is so because the embryo must be in the uterus and near the mother.
ἐν μὲν οὖν τοῖς ζῳοτοκουμένοις ἡ ὑστέρα ἐν τῇ μητρί ἐστιν, ἐν δὲ τοῖς ᾠοτοκουμένοις ἀνάπαλιν, ὥσπερ ἂν εἴ τις εἴποι τὴν μητέρα ἐν τῇ ὑστέρᾳ εἶναι· τὸ γὰρ ἀπὸ τῆς μητρὸς γινόμενον ἡ τροφὴ τὸ ὠχρόν ἐστιν.
In viviparous animals, then, the uterus is in the mother, but in oviparous animals it is the reverse, as if one were to say that the mother is in the uterus; for the yolk, which is the nourishment derived from the mother, is what represents her.
αἴτιον δ’ ὅτι ἡ ἐκτροφὴ οὐκ ἐν τῇ μητρί ἐστιν.
And the cause is that the nurturing does not take place in the mother.
αὐξανομένων δὲ πρότερον ὁ ὀμφαλὸς συμπίπτει ὁ πρὸς τὸ χόριον, διότι ταύτῃ δεῖ τὸ ζῷον ἐξελθεῖν, τὸ δὲ λοιπὸν τοῦ ὠχροῦ καὶ ὁ ὀμφαλὸς ὁ εἰς τὸ ὠχρὸν ὕστερον.
As they grow, however, the umbilical cord leading to the chorion collapses first, because the animal must emerge this way, while the remainder of the yolk and the umbilical cord leading to the yolk collapse later.
δεῖ γὰρ ἔχειν τροφὴν εὐθὺς τὸ γενόμενον· οὔτε γὰρ ἀπὸ τῆς μητρὸς τιτθεύεται, δι’ αὑτοῦ τε οὐκ εὐθὺς δύναται πορίζεσθαι τὴν τροφήν· διόπερ ἐντὸς εἰσέρχεται τὸ ὠχρὸν μετὰ τοῦ ὀμφαλοῦ, καὶ περιφύεται ἡ σάρξ.
For the newly born animal must have nourishment immediately; for it is not suckled by the mother, nor is it able to provide nourishment for itself immediately; wherefore the yolk enters within along with the umbilical cord, and the flesh grows around it.
τὰ μὲν οὖν ἐκ τῶν τελείων ᾠῶν γινόμενα θύραζε τοῦτον γίγνεται τὸν τρόπον ἐπί τε τῶν ὀρνίθων καὶ τῶν τετραπόδων, ὅσα ᾠοτοκεῖ τὸ ᾠὸν τὸ σκληρόδερμον.
In this manner, then, those that are produced from perfect eggs come forth, both in the case of birds and of those four-footed animals that lay hard-shelled eggs.
διάδηλα δὲ ταῦτα μᾶλλον ἐπὶ τῶν μειζόνων· ἐν γὰρ τοῖς ἐλάττοσιν ἀφανῆ διὰ μικρότητα τῶν ὄγκων ἐστίν.
And these things are more distinct in the larger animals; for in the smaller they are imperceptible because of the smallness of their bulk.