LOWER CRETACEOUS. 585 



C 17, D 16. HONDURAS AND COSTA RICA. 



Sapper *®^* describes certain strata of southern Central America as the Metapan 

 terrane, and says: 



Under this name I included in describing the geologic formations of Guatemala a system 

 of clays, marls, sandstones, and conglomerates with included limestone beds which con- 

 formably underlie the Cretaceous limestone. In Honduras the same formations occur with 

 the same lithologic character and they have great extent in all the northern and middle districts; 

 that they belong to the lower Cretaceous is shown by many fossils which have courteously 

 been described by Dr. Joh. Bohm of Berlin. 



In a footnote Sapper gives the following list of fossils as having been determined 

 by Bohm: 



From Carizal: 



Glauconia cfr. picteti Coqu. 

 Between Charizal and Cuevas: 



Protocardia cuevasensis n. sp. 



P. ventrosa n. sp. 



Lima wacoenaia P. Roem. 

 Prom Cuevas: 



Lima wacoensis P. Roem. 



Area elongatior n. sp. 



Protocardia cuevasensis n. sp. 



The most important places at which fossils have been found occur in the interbedded 

 Umestone strata near Selila, near Neambar, between Comayagua and Potrero, as well as between 

 Espinas and Esquias. The fossils are, however, not sufficiently numerous and not sufficiently 

 widely distributed to give definite data as to the age of individual beds, and as the petro- 

 graphic character of the Metapan terrane is often extraordinarily similar to that of the Upper 

 Triassic Tegucigalpa formation, I have not been able to determine with certainty in regard to 

 the occurrence in the departments of Tegucigalpa and Olancho whether we have to deal with the 

 Metapan or the Tegucigalpa terrane. 



The Metapan terrane is conformably overlain by a moderate thickness of Upper Cretaceous 

 ["Meso-Cretaceous," Comanche] limestones, which in Honduras often form the mountain 

 summits. * * * The limestones near the western boundary of the Repubhc of Honduras 

 near Copan, are characterized by well-preserved Rudistes, and thus belong to the Upper Creta- 

 ceous ["Meso-Cretaceous," Comanche]. The correlation of the limestones which occur in the 

 departments of Santa Barbara, Comayagua, Yoro, and Olancho and have a thickness of several 

 hundred meters with the Upper Cretaceous depends simply on the fact that they lie conformably 

 upon the Metapan terrane. 



Cretaceous limestones have not been certainly identified in the Republic of Nicaragua, but 

 it seems to me quite possible that the limestones of the middle course of the Rio Coco may be 

 so correlated. 



Sapper then goes on to mention occurrences in Costa Rica and, quoting R, T. 

 Hill, describes a dark-blue massive limestone which outcrops in steeply dipping 

 beds and is in large part composed of Rudistes and Inoceramus. He mentions 

 several other localities in Costa Rica at which rocks of probable Cretaceous age 

 occur. 



D-E 15-16. GUATEMALA AND CHIAPAS. 



The IVIesozoic formations of Guatemala are described by Sapper,^*'* who says: 



The Mesozoic formations occupy very extensive areas in Alta Verapaz (Guatemala), but 

 the strata are nevertheless very monotonous and consist everywhere of limestones and dolo- 

 mites, together with conglomerates and breccias of the same rocks, so that it is impossible to 

 distinguish different horizons by lithologic differences. 



