and the Sunnyside Arch
This and other mid-block alleyways lead to the lush communal courtyards tucked away inside the blocks of row houses here in Sunnyside Gardens. You can probably get a better sense of things from an aerial view of the neighborhood.
According to a fellow pedestrian, this bizarre-looking sidewalk column is one of two kiosks built by some community group here in Sunnyside a while back to provide people with a place to legally post announcements, ads, and the like. The group has since dissolved, and now there's no one responsible for maintaining these monstrosities. The adjacent Italian restaurant has stepped in and adopted this one — hence the color scheme.
The yellow, pollen-producing stamina and the red, five-headed, pollen-receiving stigma both emerge from the stalk-like style. A pollen grain that lands on the stigma and germinates will grow a long pollen tube that reaches down through the style to an ovule in the flower's ovary, located at the base of the style, where fertilization occurs.
See all those people in the background? That's what happens when you get too close to the wall.
(If you're curious, you can take a look at the "dangerous condition" for yourself.)