Seems to be rope and wax filler between the hood and supports
Just a lil nugget I wanted to share
Pontriac Dreams all

it looks to be just the sealant used to glue the outer skin to the inner reinforcement.

agree its just a foam like glue i guess the hide it better on the newr cars  it actually comes off quite easy

anti rattle sealant

I need some of that stuff. I'd love to know what it's called so I can buy some.

PL premium construction glue works great and looks factory, comes in a caulking tube.

you can still buy similar material some new sealants urathanes are better than the old