The rediscovery of part of the Ceres Hispanica collection of M. Lagasca and S. R. Clemente.

Thirty sheets of Gramineae, recently found in the Real Colegio Alfonso XII of San Lorenzo de El Escorial, belong to Lagasca & Clemente's Ceres Hispanica herbarium. The main corpus of the Ceres Hispanica collection is kept in the Real Jardin Botanico de Madrid, and the missing sheets were reported as having disappeared in 1823. The importance of the rediscovered material is evaluated from the point of view of its historical relevance.