by dragging a wheat straw over the membrane to see if it would catch on a perforation.

Rav Sheizvi said: Our geese are considered like water birds. If the skull of a goose is broken, even if the membrane is not perforated, it is a tereifa.

§ The mishna states: In a case where a bird fell into the fire and its innards were singed, if they turned green the bird is a tereifa; if they are red the bird is kosher. Rabbi Yoḥanan says in the name of Rabbi Yosei ben Yehoshua: The measure of their turning green is like the measure of their perforation. Just as their perforation in any amount renders them a tereifa, so too their turning green in any amount renders them a tereifa.

Rav Yosef, son of Rabbi Yehoshua ben Levi, asked Rabbi Yehoshua ben Levi: If a liver turned green on the side facing the intestines, what is the halakha? Rabbi Yehoshua ben Levi said to him: The bird is a tereifa. Rav Yosef said to him: But this halakha should be no more stringent than that of a case where the liver was removed and an olive-bulk remained (see 54a), in which case the bird is kosher. Therefore, as long as an olive-bulk remains red, the bird should be kosher. Rava said: Since the liver turned green facing the intestines, it is certain that the bird fell into the fire and the intestines themselves were singed, and this is why the animal is a tereifa, not because of the liver per se.

The Gemara recounts: Rabbi Yehoshua ben Levi had a certain hen that fell into the fire. After it was slaughtered, he sent it before the distinguished Rabbi Elazar HaKappar and said to him: Its innards were green, and Rabbi Elazar HaKappar deemed it kosher. Rabbi Yehoshua ben Levi asked: But didn’t we learn in the mishna: If they turned green they are unfit? Rabbi Elazar HaKappar said to him: The Sages said that if they turned green they are unfit only with regard to the gizzard, the heart, and the liver, which are naturally red. Other innards of a hen, such as the intestines, are naturally green, and a green appearance in them does not render the hen a tereifa. The Gemara notes: This is also taught in a baraita: Concerning which innards did they say that a green appearance renders the bird a tereifa? Only concerning the gizzard, the heart, and the liver.

The Gemara recounts: Rabbi Yitzḥak bar Yosef had a certain hen that fell into the fire. After it was slaughtered, he sent it before Rabbi Abbahu and said to him: Its innards were red, and Rabbi Elazar HaKappar deemed it a tereifa. Rabbi Yitzḥak bar Yosef asked: But didn’t we learn in the mishna: If they are red, the bird is kosher? Rabbi Elazar HaKappar said to him: Red innards that turned green and green innards that turned red render the animal a tereifa. The Sages said in the mishna that red innards are kosher only with regard to the heart, the gizzard, and the liver, because these organs are naturally red. Organs that are naturally green, however, render the bird a tereifa if they have turned red.

Rav Shmuel bar Ḥiyya says that Rabbi Mani says: If red organs turned green, and one boiled them and they turned red again, they are kosher. What is the reason? This proves that they were not burned; rather, smoke entered them and changed their color temporarily. Rav Naḥman bar Yitzḥak said: We, too, will say: If red organs did not turn green, and one boiled them and they then turned green, the animal is a tereifa. What is the reason? Their shame was revealed, i.e., it is evident that they were in fact burned. Rav Ashi said: Therefore, even if a bird’s innards remain red after it fell in a fire, a person may eat it only if it is boiled, to be certain that the innards will not turn green. The Gemara rejects this: But that is not so, since we do not presume the existence of a flaw without evidence.

§ The mishna states: If a person trampled the bird, or slammed it against a wall, or if an animal crushed it, and it lasted twenty-four hours, and then one slaughtered it, it is kosher. Rabbi Elazar ben Antigonus says in the name of Rabbi Elazar, son of Rabbi Yannai: Both this and that, i.e., all of the above cases, require inspection after slaughter, to ascertain that there is no injury that would itself render the animal a tereifa.

MISHNA: And these are kosher among birds: If a bird’s windpipe was perforated or cracked lengthwise; or if a weasel struck the bird on its head in a place that does not render it a tereifa; or if the crop was perforated. Rabbi Yehuda HaNasi says: It is kosher even if the crop was removed. If the bird’s intestines emerged from the abdominal wall but were not perforated, or if its wings were broken, or if its legs were broken, or if the feathers on its wings were plucked, the bird is kosher. Rabbi Yehuda says: If the down covering its body was removed, it is a tereifa and unfit for consumption.

GEMARA: The Sages taught in a baraita: There was an incident involving Rabbi Simai and Rabbi Tzadok, who went to intercalate the year in Lod, and they spent Shabbat in the town of Ono. And they ruled with regard to an animal whose womb was removed, in accordance with the opinion of Rabbi Yehuda HaNasi in the mishna with regard to the crop.

A dilemma was raised before the Sages: What is the meaning of the baraita? Is it referring to two different rulings, i.e., that they ruled with regard to the womb to prohibit it, and they also ruled in accordance with the opinion of Rabbi Yehuda HaNasi with regard to the crop to permit it? Or perhaps it is referring to only one ruling, and it means that they ruled with regard to the womb to permit it, in accordance with the opinion of Rabbi Yehuda HaNasi with regard to the crop, but they do not hold in accordance with the opinion of Rabbi Yehuda HaNasi with regard to the crop itself. The Gemara concludes: The dilemma shall stand unresolved.

Rabba says, and some say it was Rabbi Yehoshua ben Levi who says: The roof the crop is treated like the gullet, i.e., it renders the bird a tereifa if perforated in any amount. The Gemara asks: Where is the roof of the crop? Rav Beivai bar Abaye said: It is any part of the crop that stretches with the gullet.

§ The mishna states: If the bird’s intestines emerged from the stomach wall but were not perforated, the bird is kosher. Rabbi Shmuel bar Rav Yitzḥak says: The Sages taught this halakha only in a case where one did not jumble them, but returned them to the stomach in their proper order. But if he jumbled them, the bird is a tereifa, as it is written: “Has He not made you, and established you?” (Deuteronomy 32:6). The verse teaches that the Holy One, Blessed be He, created established locations for each organ in a person, so that if one of them is switched he cannot live. The same applies to other creatures.

It is taught in a baraita: Rabbi Meir would say that the verse: “Has He not made you, and established you?” teaches that the Jewish people is a city with everything in it. Out of it come its priests, out of it come its prophets, out of it come its chiefs, out of it come its kings, as it is stated: “Out of them shall come forth the cornerstone, out of them the stake, out of them the battle bow, out of them every master together” (Zechariah 10:4).

The Gemara recounts an incident involving a certain Roman who saw a certain man fall from the roof to the ground, and his stomach ruptured and his intestines emerged. The Roman brought the man’s son and slaughtered him before his father’s eyes