GEOLOGY OF GUATEMALA AND SPANISH HONDURAS 515 
. South of San Pedro Sula, at Chamelecon, intensely folded mica 
schist is exposed. The foliation strikes N. 80° E. South of Cha- 
melecon and of the Chamelecon River, crystalline limestones, in 
which no trace of bedding or of fossils were found, extend from 
Dos Caminos to Potrerillos, the terminus of the National Railroad. 
One mile south of La Pimienta the limestone is overlain by volcanic 
ash and by lava flows. Sapper maps the timestone as Upper Cre- 
taceous.* 
In the Sierra de Pija between the Ulua River and Trujillo 
igneous and metamorphic rocks were found in every stream exam- 
ined. Tonalites and porphyries are the most common igneous 
rocks, with paleovolcanics on the west, especially in the vicinity of 
La Ceiba and in the Congrejal Valley south of La Ceiba. The 
metamorphic rocks of sedimentary origin are schists and slates with 
cleavage striking N. 60° E. parallel to the range. 
The Bay Islands, lying 20 to 35 miles off the north shore of 
Honduras, consist of three large islands, Utilla, Ruatan, and 
Bonacca (Fig. 1), with several small islands and cays. While the 
axes of the large islands are not quite parallel, they are all part of 
the Sierra de Omoa. Historically the islands are known from the 
fact that Columbus landed on Bonacca on his fourth voyage in 
1602, and from the fact that they are inhabited by English- . 
speaking people and were not ceded to Honduras by Great Britain 
until 1860. 
Bonacca Island is ro miles long and 25 miles in maximum width, 
and the highest elevation is 1,200 feet. According to Sapper the 
island is composed of mica schist with serpentine (marble?) on 
the western end. Ruatan is 33 miles long, 3 miles wide, and the 
highest elevation is 800 feet. Sapper found mica schist with some 
crystalline limestone and amphibolite on the island.? Utilla is 74 
miles long and 23 miles wide. The western two-thirds of the island 
is composed of coral reefs, lagoons, and swamps, but the eastern 
third consists of a rolling upland averaging 4o feet in height, 
surmounted by Pumpkin Hill, 290 feet high, and Stuert Hill, 169 
feet high. The rolling surface is underlain by olivine basalt flows. 
1 Peterm. Mitt., Erginzungsheft 32, Heft 151 (1905), geologic maps. 
2 Ibid. (1905), pp. 17-18. 
