What is significant about the description at the beginning of Section 9?

The description at the beginning of Section 9 is most unlike any of the other scenes because this one is pervaded by darkness. In the introduction to Section 8, there is a hint of something deathly hanging over the scene, but with this section's introduction it seems as though death may have passed, as revealed by the ending of the Thrush's song and the worm returning to its black hole. However, the notion of darkness is clearly the most prevalent in this introduction. The overwhelming presence of darkness is not necessarily comforting, but the reader should be forced into realizing that it is, nevertheless, a part of every day.