Reference for Bekhorot 6:8
נִשְׁבַּר עֶצֶם יָדוֹ, וְעֶצֶם רַגְלוֹ, אַף עַל פִּי שֶׁאֵינוֹ נִכָּר. מוּמִין אֵלּוּ מָנָה אִילָא בְיַבְנֶה, וְהוֹדוּ לוֹ חֲכָמִים. וְעוֹד שְׁלשָׁה הוֹסִיף. אָמְרוּ לוֹ, לֹא שָׁמַעְנוּ אֶת אֵלּוּ. אֵת שֶׁגַּלְגַּל עֵינוֹ עָגוֹל כְּשֶׁל אָדָם, וּפִיו דּוֹמֶה לְשֶׁל חֲזִיר, וְשֶׁנִּטַּל רֹב הַמְדַבֵּר שֶׁל לְשׁוֹנוֹ. וּבֵית דִּין שֶׁל אַחֲרֵיהֶן אָמְרוּ, הֲרֵי אֵלּוּ מוּמִין:
If its foreleg or hind leg were broken even if [the break] is not discernable. These [last mentioned] are the blemishes that Ilah of Yavneh enumerated, and the Sages agreed with him. He added another three and they told him, we have never heard of these: One whose iris is round like that of a human, or whose mouth looks like a pig's or if most of the front [lit. "speaking"] part of the tongue has been removed. Subsequent courts said: these are blemishes.