it could just be a really dark version of the scene with the guy who has smoke pouring out/off his helmet , i was one of the people that kept askin for the serpent image , and i can see in the first image what people may be talkin about but not the second , the second i think looks more like the helmet smoking
and if ridley hadnt confirmed that giger was only involved in set pieces then i could very well have believed that there would be a giant grey pussy kickin about .