Mishnah Negaim 8:6: Two Beharot, one impure and one pure, [if the Nega] spread from this one to the other one, and afterwards it spread over his entire [body], he becomes pure. [If one was] on his upper lip [and the other] on his lower lip, [or] on two of his fingers, [or] on two [halves] of his eyelids, even though they are stuck together this one to the other one and they appear like one [Baheret], he becomes pure [if it later spreads over his entire body]. If it spread over his entire [body] but not over [an area with] a Bohak [dull blemish], he becomes impure, [but if] the tips of the limbs returned [from being covered and became] a sort of Bohak, he is [still] pure. [If] the tips of the limbs returned from [an area] less than a lentil, Rabbi Meir declares impure. But the Sages say: A Bohak less than [the size of] a lentil is a sign of impurity in the beginning, but is not a sign of impurity in the end.

שְׁתֵּי בֶהָרוֹת, אַחַת טְמֵאָה וְאַחַת טְהוֹרָה, פָּרְחָה מִזּוֹ לָזוֹ וְאַחַר כָּךְ פָּרְחָה בְכֻלּוֹ, טָהוֹר. בִּשְׂפָתוֹ הָעֶלְיוֹנָה, בִּשְׂפָתוֹ הַתַּחְתּוֹנָה, בִּשְׁתֵּי אֶצְבְּעוֹתָיו, בִּשְׁנֵי רִיסֵי עֵינָיו, אַף עַל פִּי שֶׁמְּדֻבָּקִים זֶה לָזֶה וְהֵם נִרְאִים כְּאֶחָד, טָהוֹר. פָּרְחָה בְכֻלּוֹ, אֲבָל לֹא בַבֹּהַק, טָמֵא. חָזְרוּ בוֹ רָאשֵׁי אֵבָרִים כְּמִין בֹּהַק, טָהוֹר. חָזְרוּ בוֹ רָאשֵׁי אֵבָרִים פָּחוֹת מִכָּעֲדָשָׁה, רַבִּי מֵאִיר מְטַמֵּא. וַחֲכָמִים אוֹמְרִים, בֹּהַק פָּחוֹת מִכָּעֲדָשָׁה, סִימַן טֻמְאָה בַתְּחִלָּה, וְאֵין סִימַן טֻמְאָה בַסּוֹף:

Mishnah Negaim 8:7: [If] he comes in [to the priest initially] completely white [with a Nega], he should be quarantined. [If] he develops [two] white hairs, he should be decided [as impure]. [If later] both of them blacken or [only] one of them, [or] both of them shorten or [only] one of them, [or] a boil becomes adjacent to both of them or to one of them, [or] a boil surrounds both of them or one of them, or [the boil] divides them, [whether it was] a boil, a partially healed boil, a burn, a partially healed burn, or a Bohak, [he is pure]. [If] he [instead] develops a patch of healthy skin or white hair, he is impure. If he does not develop a patch of healthy skin nor white hair, he is pure. But in all cases in which the tips of his limbs returned [from being covered], behold they are like they were [in terms of purity status]. If [the Nega] spread over part of his [body], he is impure. [If] it spread of his entire [body], behold he becomes pure.

הַבָּא כֻלּוֹ לָבָן, יַסְגִּיר. נוֹלַד לוֹ שֵׂעָר לָבָן, יַחְלִיט. הִשְׁחִירוּ שְׁתֵּיהֶם אוֹ אַחַת מֵהֶן, הִקְצִירוּ שְׁתֵּיהֶן אוֹ אַחַת מֵהֶן, נִסְמַךְ הַשְּׁחִין לִשְׁתֵּיהֶן אוֹ לְאַחַת מֵהֶן, הִקִּיף הַשְּׁחִין אֶת שְׁתֵּיהֶן אוֹ אֶת אַחַת מֵהֶן, אוֹ חִלְּקָן הַשְּׁחִין וּמִחְיַת הַשְּׁחִין הַמִּכְוָה וּמִחְיַת הַמִּכְוָה וְהַבֹּהַק. נוֹלַד לוֹ מִחְיָה אוֹ שֵׂעָר לָבָן, טָמֵא. לֹא נוֹלַד לוֹ לֹא מִחְיָה וְלֹא שֵׂעָר לָבָן, טָהוֹר. וְכֻלָּן שֶׁחָזְרוּ בָהֶן רָאשֵׁי אֵבָרִים, הֲרֵי אֵלּוּ כְמוֹת שֶׁהָיוּ. פָּרְחָה בְמִקְצָתוֹ, טָמֵא. פָּרְחָה בְכֻלּוֹ, הֲרֵי הוּא טָהוֹר: