1) WHY A "TUMTUM" DOES NOT PERFORM CHALITZAH
QUESTION: In the Mishnah (81a), Rebbi Yehudah states that a Tumtum does not perform Chalitzah even if he is found to be a male, because he has the status of a Seris (a "Seris Chamah," who is a Seris from birth) who is exempt from Chalitzah. The Gemara cites the opinion of Rebbi Yosi b'Rebbi Yehudah who says that a Tumtum may not perform Chalitzah because perhaps he has the status of a "Seris Chamah." The Gemara points out that Rebbi Yehudah and Rebbi Yosi b'Rebbi Yehudah disagree about a case in which the dead husband has no brothers except for the Tumtum. According to Rebbi Yehudah, the Yevamah may remarry without Chalitzah. According to Rebbi Yosi b'Rebbi Yehudah, the Yevamah may not remarry until she performs Chalitzah (mi'Safek) with the Tumtum, since the Tumtum is only a doubtful Seris.
RASHI earlier (81a) comments that when Rebbi Yehudah in the Mishnah states that a Tumtum who is found to be a male may not perform Chalitzah, he refers to "when there is another brother." This implies that when there are no other brothers to perform Chalitzah, the Tumtum does perform Chalitzah with the Yevamah.
Rashi's words are difficult to understand. The Gemara here clearly explains that according to Rebbi Yehudah, the Tumtum does not perform Chalitzah even if he is the only brother.
ANSWER: The MAHARSHA here and the YASHRESH YAKOV (81a) explain that Rashi does not mean that Rebbi Yehudah in the Mishnah refers only to a case in which there are other brothers. Certainly the same Halachah applies when there are no other brothers; the Tumtum does not do Chalitzah and the Yevamah may remarry. Rather, Rashi is making an inference from the wording of Rebbi Yehudah in the Mishnah. Rebbi Yehudah does not say about the Tumtum that "Lo Choletz" ("he does not perform Chalitzah"), as the Mishnah earlier (79b) says, which means that the Yevamah does not need Yibum or Chalitzah. Rather, he says, "Lo Yachlotz" ("he should not do Chalitzah"), which is the same wording which Rebbi Yosi b'Rebbi Yehudah uses. This implies that when there are other brothers, the Tumtum should not do Chalitzah.
This explanation, however, does not explain why Rebbi Yehudah in the Mishnah says "Lo Yachlotz." He should have said "Lo Choletz" to imply that the Tumtum does not do Chalitzah at all, even when there are no other brothers.
Apparently, Rebbi Yehudah uses this terminology to emphasize that he is responding to Rebbi Yosi b'Rebbi Yehudah, who says "Lo Yachlotz" for a different reason -- the Tumtum is a Safek Seris. Rebbi Yehudah responds that the reason the Tumtum should not perform Chalitzah is not that the Tumtum is a Safek Seris, but because he is a certain Seris. By using the term "Lo Yachlotz," Rebbi Yehudah in the Mishnah alludes to the existence of a second opinion, that of Rebbi Yosi b'Rebbi Yehudah (who indeed maintains that the Tumtum does not perform Chalitzah only when there are other brothers), without having to mention it explicitly.