Buscando en internet:
Diseños de Criss Foss para Alien:
y también he encontrado este diseño "más bulboso" de Giger:In a very early draft of the script, the eggs were originally meant to be housed in a completely separate architectural structure, shaped in the form of a massive pyramid. These illustrations of the discarded sequence were done by British illustrator and science fiction artist Chris Foss.
Saludos