and dissolves it. Rather, one examines it with oil, as oil is soft and cleans the embryo so that its sex can be discerned. And one views it only in the light of the sun.

The baraita continues: How does one examine the embryo? The Gemara expresses surprise at this question: How does one examine it to determine whether it has the halakhic status of an offspring? Clearly, one examines it as we just said. Rather, the question is as follows: In what manner does one examine it to ascertain whether it is male or whether it is female?

Abba Shaul bar Nash, and some say Abba Shaul bar Remash, says: One brings a sliver of wood whose top is smooth, and he moves it along the embryo in that place, i.e., the sex organ. If the sliver is caught, i.e., its movement is not smooth, it is known that the embryo is male, as its member interfered with the movement of the sliver. And if the sliver is not caught, it is known that it is female.

Rav Naḥman says that Rabba bar Avuh says: They taught this halakha, that if the movement of the sliver is not smooth then the embryo is male, only if the sliver was moved along the sex organ of the embryo from below to above; but if it was moved from the sides, from one side to the other, the fact that it was not smooth does not prove that the embryo is male, as one can say that the sides of the womb interfered.

Rav Adda bar Ahava says: The complete version of the baraita is taught as follows: If it was female, its vagina can be discerned by the appearance of a line like a cracked grain of barley oriented along the length of its body. Rav Naḥman objects to this: But perhaps it is not the vagina but the recess between the testes, and the embryo is male. Abaye said to him: Now, at this stage of development, the testes of the embryo themselves are not discernible. Is it possible that the recess between the testes is discernible?

The baraita teaches that at this stage an embryo does not have the shape of arms and legs. Rabbi Amram says that it is taught in a baraita that when an embryo’s arms and legs start to take shape, its two thighs look like two strings of crimson thread [zehorit]. And Rabbi Amram says with regard to this matter that the thighs look like two strings of the woof, which are thicker than those of the warp. The baraita adds: And its two arms look like two strings of crimson thread. And Rabbi Amram says with regard to this matter that the arms look like two strings of the warp.

Shmuel said to Rav Yehuda: Shinnana, do not perform an action, i.e., do not issue a practical ruling deeming a woman who discharges an embryo at this stage of development impure, unless the embryo has grown hair. The Gemara asks: And did Shmuel actually say that? But doesn’t Shmuel say with regard to a woman who discharged a gestational sac that both in this case, where the amniotic fluid is turbid, and in that case, where the fluid is clear, the woman must be concerned that the discharged gestational sac might have the status of an offspring, which would mean that she is impure even without the growth of hair on the embryo?

Rav Ami bar Shmuel says: This matter was explained to me by Mar Shmuel: As for being concerned that perhaps she is impure, the woman must be concerned, due to the uncertainty whether she discharged an offspring. But we do not give her the days of purity that follow the period of impurity for a woman who gave birth, unless the embryo has grown hair.

The Gemara asks: Is that to say that Shmuel is uncertain whether a gestational sac has the halakhic status of an offspring? But there was an incident involving a certain gestational sac that was brought before Mar Shmuel, and Shmuel said: This embryo is forty-one days old. And Shmuel subsequently calculated the amount of time that had passed from the day that the woman went to perform immersion in a ritual bath until that day, and it was only forty days.

And he said to the local court: This husband engaged in intercourse with his wife when she was a menstruating woman. They bound the husband and he confessed. Since Shmuel was so proficient in embryology, why was he unsure about the halakhic status of a gestational sac? The Gemara answers: Shmuel himself is different, as his strength, i.e., his proficiency, was great. His general ruling that the halakhic status of a gestational sac is uncertain applies to people who are not as proficient as he is.

§ The mishna teaches that a woman who discharges a sandal fetus or one who discharges an afterbirth observes the strictures of a woman who gave birth both to a male and to a female. The Sages taught in a baraita: A sandal fetus has a similar appearance to a certain fish of the sea known as a sandal fish;it looks as though it is a full-fledged offspring from the outset, but it was mashed. Rabban Shimon ben Gamliel says: A sandal fetus has an appearance that is similar to the tongue of the large bull. Students testified in the name of our teachers that for a sandal fetus to have the halakhic status of an offspring, it requires the shape of a face.

Rav Yehuda says that Shmuel says: The halakha is that a sandal fetus requires the shape of a face for it to have the status of an offspring. Rav Adda says that Rav Yosef says that Rabbi Yitzḥak says: A sandal fetus requires the shape of a face, but the face does not need to be in its proper location; even if the face is on the back of its head, the fetus has the status of an offspring. A parable to which this situation can be compared is that of a person who slapped another in the face and pushed his face back. Here too, the face of the sandal fetus was pushed back due to external pressure.

The Gemara relates: In the days of Rabbi Yannai, the other Sages wished to deem pure a woman who discharges a sandal fetus that does not have the shape of a face. Rabbi Yannai said to them: You have deemed pure women who discharge offspring. Rabbi Yannai holds that even a sandal fetus that does not have the shape of a face is considered an offspring.

The Gemara asks: But isn’t it taught in a baraita that students testified in the name of our teachers that for a sandal fetus to have the halakhic status of an offspring it requires the shape of a face? Rav Beivai bar Abaye says that Rabbi Yoḥanan says in response: This mishna, i.e., the ruling to which the students testified, is taught from the testimony of Rabbi Neḥunya. In other words, this ruling is the opinion of an individual tanna, which is not accepted. Rabbi Zeira says: Rav Beivai merited that his ruling of halakha, which he transmitted in the name of Rabbi Yoḥanan, was accepted. As he and I were both sitting before Rabbi Yoḥanan when Rabbi Yoḥanan said this halakha, but Rav Beivai said it first to the other Sages, and thereby merited that it was ascribed to him.

§ The Gemara asks: Why does the mishna mention that if a woman discharged a sandal fetus she observes the strictures of a woman who gave birth both to a male and to a female? Since there is no such thing as a sandal fetus that does not have another offspring with it, which mashed it and gave it the form of a sandal fish, in any case the woman has the impurity of a woman after childbirth.

The Gemara answers: If it is a female offspring that is born with the sandal fetus, it is indeed unnecessary to mention the halakha of the sandal fetus, as the woman is in any case impure for two weeks. But here we are dealing with a case where a male is born with it, on account of which the woman would be impure for only seven days were it not for the sandal fetus.

In this case, it is necessary for the mishna to state that the woman observes the strictures of one who gave birth both to a male and to a female, lest you say that since Rav Yitzḥak bar Ami says that the sex of a fetus is determined at the moment of conception, as, if the woman emits seed first she gives birth to a male and if the man emits seed first she gives birth to a female, therefore, it can be concluded from the fact that this offspring that was born with the sandal fetus is male, that this sandal fetus is also male.

Lest this reasoning be accepted, the mishna teaches us that the woman must observe the strictures of a woman who gave birth to a female as well. This is because one can say that perhaps both the man and the woman emitted seed at the same time, and consequently this offspring is male and that sandal fetus is female.

Alternatively, it can be suggested that it is necessary for the mishna to state this halakha even with regard to a case where the twin of the sandal fetus is female, as, if the woman gives birth to the female before sunset and gives birth to the sandal fetus after sunset, which is considered the next day, the sex of the sandal fetus affects the count of the woman’s periods of impurity and purity.

If the sandal fetus is male, the woman’s status as a woman after childbirth ends after the eightieth day from the birth of the female offspring, and she counts the beginning of the period when seeing blood renders her impure as a menstruating woman from the birth of the first offspring, i.e., the female. But if the sandal fetus is female, the woman has the status of a woman after childbirth until after the eightieth day from its birth, which is the eighty-first day from the birth of the first offspring. If so, she counts the beginning of the period when seeing blood renders her impure as a menstruating woman from the birth of the last offspring, i.e., the sandal fetus.

The Gemara discusses why the case of a woman who discharged a sandal fetus is mentioned in other mishnayot, given that a sandal fetus always has a twin. First the Gemara discusses the halakha of a woman who discharged a sandal fetus that we learned in a mishna