The most famous and evocative image in Un Chien Andalou is that of the Woman's eyeball being sliced by Buñuel in the first scene. By cutting to a close-up of an animal's eye (by Buñuel's own account it was a calf's eye) being sliced, Buñuel could immediately evoke a visceral experience in the viewer. This image presages the other visceral shocks, particularly those involving trauma to the body, found throughout the film.
The Ants Crawling out of the Man's Hand
This image, supposedly originating in a dream of Dalí's, appears twice in the film: when the Woman turns around and sees the First Man examining his own hand, and when the Woman escapes into another room from the First Man's assault on her, shutting the door on that man's hand. As with the close-up of the sliced eyeball, the close-up of the ants crawling out of the hand conveys a visceral shock characteristic of images of trauma to the human body.
Buñuel relies on dissolves in order to convey associations between shots. For example, a shot of the ants crawling out of the First Man's hand dissolves into a shot of a woman's armpit on a beach, which then dissolves into a shot of a sea urchin, which then dissolves into an iris shot of the androgynous figure poking the severed hand with a stick. Because these dissolves allow for slower transitions than direct cuts, they are able to mimic the way in which the imagination (as in moments of free association) can move between related images.
The dead donkeys
Another of the film's viscerally shocking images is that of the dead, decomposing donkeys atop the grand pianos that the First Man pulls by two chords. The donkeys are missing their eyes: an image that should of course be compared with that of the sliced eyeball at the beginning of the film. But in this shot's association between sex and death (as the First Man had just been sexually assaulting the Woman), this shot should also be compared with that of the First Man at the beginning of the assault, as he grabs the Woman's breast, staring up at her with a dead look in his eyes that Buñuel himself later described as a "death mask" (Buñuel, My Last Sigh, Chapter 2). Dalí titled a 1928 painting of his The Rotting Donkey.
Un Chien Andalou Questions and Answers
The Question and Answer section for Un Chien Andalou is a great
resource to ask questions, find answers, and discuss the novel.