That sixteenth portion is subtile. It should be known as Soma. It is never upheld by the senses. On the other hand, the senses are upheld by it.
षोडशी तु कला सूक्ष्मा स सोम उपधार्यताम्। न तूपयुज्यते देवैर्देवानुपयुनक्ति सा॥