When the members of the “Jorullo Excursion” of the Tenth International Geological Congress were in the city of Morelia, in Mexico, they visited the College of St. Nicholas (founded in 1540), in the buildings of which is the Museo Michoacano. One of the most interesting objects in the Museum in question is a piece of basaltic lava containing remains of maize, which has been described by Dr. M. M. Solórzano, the Curator of the Museum, in an article entitled “Breve noticia acerea de algunos productos volc´nicos de las immediaciones de esta ciudad” in the “Boletin de la Sociedad Michoacana de Geographia y Estadistica,” Tomo ii, Núm. 8, Morelia, Julio 15 de 1906, pp. 59, 60.