520 SIDNEY POWERS 
limestone ridge at Livingston, and Lake Izabal (Fig. 4). The 
fossils collected were identified by Dr. Paul Bartsch as the fresh- 
water gastropod Sphaeromelania lacustris Morelet (?).t Lignite 
beds 2 to 3 feet thick occur in several streams emptying from the 
south into the Gulfete and Laguna between Rio Dulce and Lake 
Izabal—Rio Lampara, Rio Frio, Rio Juan Vicente—and lignite 
beds are reported near Livingston east of the Rio Dulce limestone. 
The white clays and lignite beds may have a thickness of a few 
hundred feet. They are folded, dips as high as 8 degrees being 
observed. Rounded chert bowlders, apparently similar to those 
associated with these clays, are reported by Sapper to be associated 
with chalk and limestone in northern Yucatan and in British 
Honduras between Belize and Orange Walk. 
British Honduras.—Southern British Honduras is underlain by 
a continuation of the Oligocene Rio Dulce limestone and of the 
Cretaceous limestone of Guatemala. Prominent ridges of lime- 
stone, probably the Rio Dulce limestone, form the hills along the 
Sarstoon River near the southwest corner of British Honduras and 
at Punta Gorda, British Honduras, on the coast. North of Punta 
Gorda the flat shore is bounded by the most extensive barrier reef 
in the Atlantic Ocean. Behind the cays and reefs is the closed 
inland passage up the Yucatan Coast with narrow channels through 
the reefs. Farther north the large island Cozumel, composed of 
limestone reefs elevated 10 to 30 feet above sea-level, lies off the 
flat, monotonous coast of Yucatan. 
Geological observations on British Honduras have been made 
by Sapper and by others.?, The Cockscomb Mountains of British 
Honduras are described as a horst about 45 miles in diameter with 
mountains as high as 3,050 feet. Sapper speaks of granites and 
quartz porphyries, argillaceous schists, quartzites, and crinoidal 
Carboniferous limestone striking in a northeast to east direction. 
North of these mountains and extending over the large department 
Peten, Guatemala, late Tertiary limestones are so soluble that the 
* Collected near Rio Frio. From shells eaten by the Indians Dr. Bartsch iden- 
tified Ewglandina carminensis Morelet, Sphaeromelania corvina Morelet, S. glaphyra 
immenis Morelet, and S. glaphyra Morelet. 
2 Peterm. Mitt., Erginzungsheft 27, Heft 127, 1899; E. Suess (de Margerie), 
La Face de la terre, III (3) (Paris, 1913), pp. 1264-74. 
