(Mishnah): If Reuven sat in the doorway and did not fill it, and Shimon sat [next to him] and filled it (trapping a deer in the house), Shimon is liable;

If Reuven sat in and filled [the width of] the doorway, and Shimon sat next to him (and also filled the width), even if Reuven left and Shimon remained, Reuven is liable and Shimon is exempt;

[Shimon] is like one who locked his house to guard the contents, and a deer was found inside.

(Gemara - R. Shamai) Question: May one put food in front of [a deer that entered one's house in the way that the Mishnah discusses, on Shabbos]? (PNEI MOSHE)

Answer: [No,] like a Mishnah teaches that one may not put water in front of bees or in front of doves in a dovecote, for we do not make solutions for something not prepared. The same applies here.

Question (R. Shamai): May one put a Kli over [a bird that became trapped in one's house on Shabbos]?

Answer: [Amora'im argue about this,] like R. Shimon bei R. Yanai said - I did not hear this from my father. My sister told me in his name that an egg laid on Yom Tov, one may support it with a Kli, lest it roll, but one may not put a Kli over it;

Shmuel said that one may put a Kli over it.

Question (R. Shamai): May one tie it with a rope?

Answer: This is like R. Shimon ben Elazar permitted to use sides of a tree on Shabbos. The same applies to sides of a tree and sides of an animal. Whenever one may use sides of an animal, one may tie it. Whenever one may not use sides of an animal, one may not tie it. (I.e. it is permitted - PNEI MEIR.)

(Mishnah): If one traps or wounds any of the eight Sheratzim listed in the Torah he is liable;

Regarding other Shekatzim u'Rmasim (vermin) -- If one wounds them he is exempt;

If he traps them for a need he is liable. If it was not for a need, he is exempt.

Animals or birds in his Reshus, one who traps them is exempt. One who wounds them is liable.

(Gemara - R. Zerikan citing R. Yehudah): R. Yochanan and Reish Lakish argue about this. One of them said that all agree [to our Mishnah], and one said that it is an argument (it is like R. Yochanan ben Nuri, and unlike Rabanan.) We do not know who said this and who said this.

(R. Ze'ira): We will explain the words of our Rebbeyim from their words;

(Mishnah): The following skins are like the flesh - skin of man and domestic pigs;

R. Yosah says, even skin of a wild pig [is like the flesh. R. Yochanan ben Nuri says, the skin of all eight Tamei Sheratzim is Tahor.]

(R. Yochanan): This is only for Isur [to eat it] and Tum'ah, but for lashes (for eating it), it is skin, and one is not lashed for it for Neveilah. (Mid'Oraisa, all agree that it is skin, and also for Shabbos. They argue about whether or not Chachamim decreed Tum'ah and Isur.)

(Reish Lakish): Rebbi taught a complete Mishnah - it is for Isur and for lashes and for Tum'ah. (The Tana'im argue about whether or not it is considered skin mid'Oraisa, and also for Shabbos. We explained this like PNEI MOSHE.)

A Beraisa supports this one (R. Yochanan), and a Beraisa supports this one (Reish Lakish);

A Beraisa supports R. Yochanan. The eight Sheratzim have skin [so one who wounds them on Shabbos is liable];

R. Yochanan ben Nuri says, therefore I say that the eight Sheratzim have skin [also for Isur and Tum'ah].

A Beraisa supports Reish Lakish. One who wounds Sheratzim [on Shabbos] - for those that have skin, he is liable. For those that do not have skin, he is exempt;

R. Yochanan ben Nuri says, the eight Sheratzim have skin. (This shows that they argue about Shabbos.)

(R. Yosi bei R. Bun citing Rav): It is skin, and one is not lashed for it for Neveilah.

This is like R. Yochanan taught.

One who traps worms, flies, wasps or mosquitoes is liable. R. Yehudah exempts;

And so R. Yehudah used to say, that one is liable only for something normally trapped.

One who traps grasshoppers when there is dew (they cannot see, so it is as if they are already trapped) is exempt; [one who traps them] when it is hot, he is liable;

Elazar ben Achvai says, even when it is hot, when they are swarming [it is easy to catch them] he is exempt.

One who traps a deer that is lame, blind, sick or [very] young, he is exempt. If it was sleeping, he is liable. [While sleeping] it closes one [eye] and opens one [so it is not considered trapped].

R. Yanai forbade to kill a [Stam] wasp on Shabbos.

Support: Five may be killed on Shabbos - a Mitzri fly, a wasp [specifically!] of Ninveh, a scorpion of Hadayos, a snake in Eretz Yisrael, and a wild dog anywhere.

A case occurred in which a snake fell on Shabbos and someone from Nafat killed it. Rebbi said "it encountered someone [improper] like it.''

Question: (Why did Rebbi say so?) Is it not one of the things that one may kill on Shabbos?

Answer: That is when it is coming to damage. (This snake was not coming to damage.)

(Beraisa - R. Yakov): One who sees a snake or scorpion within four Amos, it is proper that he die through it, but Shamayim has much mercy;

R. Shimon says, when is this? It is when he did not kill them, but if he killed them, they appeared to him only so he will kill them;

Chachamim say, in either case (whether he killed them or escaped them), they appeared to him only in his merit;

It says "Shim'u Zos Kol ha'Amim Ha'azinu Kol Yoshvei Cheled'' - R. Acha in the name of R. Avahu, and Rabanan, argued about this;

One said, why are all who enter the world compared to a weasel? Rather, it is because everything on the dry land, there is [something corresponding] in the sea, and there are many species in the sea without [something corresponding] in the land, and there is no weasel in the sea.

The other said, why are all who enter the world compared to a weasel? This weasel drags [food] and deposits, and does not know for whom it deposits, so all who enter the world drag and deposit, drag and deposit, and do not know for whom they leave [their wealth] - "Yitzbor v'Lo Yeda Mi Osfam.''

(Mishnah): Animals or birds in his Reshus, one who traps them is exempt. One who wounds them is liable.

Limitation: This is only if they are in [that] person's (i.e. the owner's) Reshus. If they are not in [that] person's Reshus (e.g. they went to another's Chatzer, and he returns them to his Chatzer), he is liable.

Inference (R. Yosah): If an ox rebelled (does not let one hold it), one who traps it on Shabbos is liable. (We explained this like ARUCH HA'SHULCHAN OC 316:34.)

(Rabanan of Kisarin citing Rav Avdan): Skin of a bird, one may write a Mezuzah on it. (Since our Mishnah obligates one who wounds a bird, this shows that its skin is considered skin - PNEI MOSHE.)