As I discuss in this answer, each of the four Vedas consists of four portions: Samhitas, the core part of the Vedas which consist of verses heard from the gods; Brahmanas, which provide instructions on the proper conducting of important rituals; Aranyakas, which provide a guide to rituals meant for forest-dwellers and hermits; and Upanishads, which consist of conversations between teachers and students which clarify the philosophical message of the Vedas. But the Shukla Yajur Veda is organized differently. (There are two versions of the Yajur Veda, the Shukla or "white" version and the Krishna or "dark" version.)
The Shukla Yajur Veda only consists of two portions: a Samhita, called the Vajasaneyi Samhita, and a Brahmana, called the Shatapatha Brahmana. That doesn't mean that it's missing Aranyakas and Upanishads, just that they're located in strange places. One Upanishad, the Isha Upanishad, is actually part of the Vajasaneyi Samhita, as I discuss in this question. Another Upanishad, the Brihadaranyaka Upanishad, is part of the Shatapatha Brahmana, specifically forming Adhyayas (chapters) 4-9 of the 14th Kanda of the Shatapatha Brahmana.
But my question is about the Aranyaka of the Shukla Yajur Veda, known as the Brihad Aranyaka. According to this Wikipedia page, the Brihad Aranyaka is also part of the Shatapatha Brahmana, specifically forming Adhyayss 1-3 of the 14th Kanda of the Shatapatha Brahmana. So if Wikipedia is right, that would mean that of the nine Adhyayas of the 14th Kanda, the first three form the Brihad Aranyaka and the last six form the Brihadaranyaka Upanishad. But that doesn't make sense to me; why would the name be Brihadaranyaka Upanishad if it were separate from the Brihad Aranyaka?
Could it be that the Brihad Aranyaka constitutes the entire 14th Kanda of the Shatapatha Brahmana, making the Brihadaranyaka Upanishad part of the Brihad Aranyaka? To put it another way, is the Brihadaranyaka Upanishad an Upanishad inside of an Aranyaka inside of a Brahmana, or just an Upanishad inside of a Brahmana? (Whew!)