Musar for Bikkurim 3:10
רַבִּי שִׁמְעוֹן אוֹמֵר, שָׁלֹשׁ מִדּוֹת בַּבִּכּוּרִים, הַבִּכּוּרִים, וְתוֹסֶפֶת הַבִּכּוּרִים, וְעִטּוּר הַבִּכּוּרִים. תּוֹסֶפֶת הַבִּכּוּרִים, מִין בְּמִינוֹ. וְעִטּוּר הַבִּכּוּרִים, מִין בְּשֶׁאֵינוֹ מִינוֹ. תּוֹסֶפֶת הַבִּכּוּרִים נֶאֱכֶלֶת בְּטָהֳרָה, וּפְטוּרָה מִן הַדְּמַאי. וְעִטּוּר הַבִּכּוּרִים חַיָּב בַּדְּמַאי:
Rabbi Shimon says, there are three categories in <i>Bikkurim</i>: the <i>Bikkurim</i> themselves, the addition to the <i>Bikkurim</i>, and the adornment of the <i>Bikkurim</i>. The addition to the <i>Bikkurim</i> are from the same species. The adornment of the <i>Bikkurim</i> is from a different species. The addition to the <i>Bikkurim</i> are eaten in ritual purity, and are exempted from <i>Demai</i> [produce from which it is uncertain whether tithes were already taken]. The adornment of the <i>Bikkurim</i> are obligated in <i>Demai</i> [requiring the <i>Kohen</i> to tithe them].