Encyclopedic
This is not the only poem in which Moore draws information from a number of sources. She likes the bonus-point vocabulary words, and she doesn't discriminate against certain kinds of language or information that we might not necessarily associate with poetry. Scientific references are fair game, and so are clinical and medical words.
Remember, not only was Marianne Moore a highly educated, well-read woman, but she also worked as a librarian in New York. She had access to all kinds of information, and she made good use of all of it. And hey, why not?