The tertiary formation and particularly limestone covers the entire Department of Peten. Furthermore, limestones and dolomites of the upper cretaceous age are noted from La Libertad toward the Usumacinta River and toward British Honduras. In the localities of San Luis and Santa Bárbara there are tertiary limestones and sandstones of Eocene and miocene ages. The limestones and dolomites of the upper cretaceous age are also found in various localities mixed with tertiary limestone and sandstone as well as conglomerates, dolomites, and limestones of the lower cretaceous age. In other sections they are mixed with limestones and dolomites of the upper carboniferous age mingled with slate, sandstone and pudding stone. The latter formation is found in other sections with precarboniferous limestone and also with crystalline limestone of the azoic age. The tertiary formation is followed by an azoic formation of gneiss, mica slate, and phylada with large intrusions of granite. A kind of horn-blend slate has been observed in some parts of Izabal. [Illustration: LANDSCAPE OF GUASTOTOYA RIVER.] The eruptive formations are composed of porphyry in the north and northwest; of diorite, obsidian, rhyolite, and dacite and of trachyte, together with basalt, rhyolite, obsidian and granite in other sections. The eruptive formations are further composed of basalt in Pacaya and several other volcanoes; and mostly of ambesite in the rest of the Cordilleras and the highlands. For the present-day traveler who is interested in earthquakes and their effects and in the ruins of Spanish architecture, nothing more entertaining can be found than a visit to La Antigua, which can be reached from Guatemala City by a few hours' ride in carriage or on horseback. Antigua stretches through the beautiful and fertile valley which in the Indian language means dry lake because the tradition exists that in prehistoric times there was a fine sheet of water covering the land. The panorama which delights the eye from any elevated point of Antigua is glorious. The three volcanoes of Acatenango, Agua (water) and Fuego (fire) lose their majestic combs in the clouds. In every direction spread fertile fields with an infinite number of coffee and sugar plantations in every state of production. The borders of the city are bathed by two charming rivers, the Pensativo and the Portal. In the immediate neighborhood are hygienic baths of pure crystalline water. PREHISTORIC RUINS AND FAMED LAKE ATITLAN. Many volumes have been written about the prehistoric ruins of Guatemala and especially of Copan. One of the most recent and most sumptuously illustrated is that by Anne Cary Maudslay and Alfred Percival Maudslay entitled "A Glimpse at Guatemala." It was published in London. In this book Professor Maudslay gives the following description of a visit to the ruins at Quiriguá: