Newton street separates from West Roxbury Parkway at the left side of the image. At the east end of this segment, there are several destinations on the north side, so the path must cross a number of driveways.
The string of beads at the right side of the image is a pullchain which hung in front of the plans as they were displayed.
You may click on the image to see a larger version in which the labels are readable.
An enlargement of the cross-section drawing (at the cross-section line near the middle of the image) is here. The three detail drawings of the split are enlarged here, here, and here.