Memory of Silius is a painting from 1975, acquired by Sempere directly from the artist as a result of the intense friendship they maintained since they met in Paris in the 1950s. It belongs to a series of works in which Lucio Muñoz populated his universe with figures bearing invented names such as Silius, Mistias, Krampertiscos, or Rinopecums, beings that do not belong to the animal, plant, or mineral kingdom, but rather to a territory of the imaginary whose laws only the artist knows. For Lucio Muñoz, naming was essential: the imagination of a new being demands a name by which to know it, so that it becomes one more member of the family.

The wooden surface is worked with a complex technique: rabbit-skin glue tempera finished with oil glazes and in some areas impasto over the panel; in the cracks and grooves, oil burned with a blowtorch. All of this to construct an image of dense shadow: an almost black background in the upper area that gives way to an earthy ochre in the lower area, divided by a barely perceptible horizon line. Over that dark landscape, an amorphous and rough central form emerges like a fossilized being or a rock with latent life. The splintered and sanded wood—the artist himself noted in the preparatory drawing indications such as "very splintered crack for the character's body, minimal relief"—adds a tactile dimension that is also semantic: the material is not support but body.

Silius is a character of Kafkaesque spirit that appears in a series of works telling a story: Vegetable Silius, Silius and the Night, Sacrifice of Silius, and this Memory of Silius. Lucio Muñoz chose an important work for Sempere's collection, as the painting was exhibited at the 1976 Venice Biennale, alongside Sempere's own mobile also in the collection.