I always felt that photos did poor justice to the breathtaking dimensionality of skulls, so lets try something different. (Making animated gifs is something I’m somewhat new at, so bear with me here.)
This is a Gaboon Viper skull.
Gaboons are large (highly-venomous) African vipers, that hold the unique distinction of having the longest fangs in the world, with the ability to inject more venom than any other snake. There’s usually two (or more) fangs on each side.
In the photo below, you can see a groove at the base of the foremost fangs, through which the venom duct enters the hollow fang.