Giger's National park References concept art from Jodorowsky's Dune

leading from

HR Giger's National Park

and

Concept art for Jodorowsky's Dune showing Duke Leto attempting to poison Baron Harkonnen 

Giger's painting "National Park" from 1975.
(Possibly loosely inspired by the works of Miodrag Đurić / "Dado")

a) I'm with the idea that Giger saw the Henu Barque quality of the drawing when someone such as Jodorowksy showed it to him when had Giger working on Dune in 1975.

Souce: http://www.duneinfo.com/unseen/jodorowskys-dune-uncovered/31

a) Naked man in the poisonous clouds and the deformed skull

• a.i) The metal patch covering the man's groin becomes the eye socket of the skull which also resembles the distorted face with the eye socket become a mouth.  
• a.ii) The leg becomes the beak like protrusion which also could be a beard of the distorted face. 
• a.iii) The left arm becomes the tube like neck holding the skull. 
• a.iv) The collar becomes the point where a skull is impaled by a tusk like form and so the head of the man with his red hair doesn't make it through into the translation.
• a.v) See also: Face mutating into bird skull by way of Salvador Dali
   
  

b) Poisonous gas and bean like forms.

• b.i) This purple gas begins to resemble a colon and because of division in the gas and the lines of the wall behind, they start to seem like a mass of female behinds

c) Poisoned man collapese on floor's legs become the limbs for a mutant animal. 

• c.i) His limbs become merged with the idea that Giger had for a biomorph in his earlier illustration "Feast For The Psychiatrist - Rape"  
• c.ii See also: Multi limbed Biomorph

d.) Poisoned bald man surrounded by floor tiles becomes demon with spikes in neck

e.) Ceiling dome and hydrocephalic skull

• e.i) Ceiling dome surrounding by snake body decoration with Baron Harkonnen's head intersecting becomes the hydrocephalic skull with headgear and accompanying snak