In this essay I am dealing with the image of blood in the milk which dominates Clytemnestra’s dream in Aeschylus’s Agamemnon; my aim is to show how this imagery undermines the characters’ tendency to negate Clytemnestra’s motherhood. Αlthough the serpent bites the breast, no venom is mentioned in the text: blood seems to come from Clytemnestra’s womb and to spurt out of the nipple with the milk of the feed, not from the wound caused by the bite of the serpent. Therefore, it is hard to assume that blood clots because of venom from the serpent’s bite, rather than, having already been clotted in Clytemnestra’s womb, flowing into the milk with the feed. It seems appropriate to suppose that the image of blood in maternal milk confronts us with a situation similar to the case of the Samo’s beliefs studied by Héritier: the trace of blood in Clytemnestra’s milk might be thought of as the traces of her menstrual blood. We may, thus, assert that the play’s search for an authoritative discourse about Agamemnon in his role as Father is inevitably exposing the anxiety and the vulnerability of suppressing a matter of fact, namely that the mother’s body gives and nurtures life.