400 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. 
rocks were classed by d’Orbigny as Devonian and Carboniferous and 
in part Triassic, but he cited no fossils. Forbes says that the beds 
contain plant remains (coniferous indeterminable) and he was in- 
formed that a complete Saurian head had been extracted from the 
beds by M. Ramon Due, but was not successful in obtaining it nor 
some fossil bones and teeth now in the Museum of Avignon in France, 
sent there by M. Granier of La Paz. The character of these beds, as 
already stated in describing the Permian, is like the typical Permian 
of Russia. Forbes concluded that their age must await the finding 
of fossils. 
Raimondi (1873), in his study of the Department of Ancachs, 
classes as Jurassic certain formations containing coal and yielding 
ammonite fossils. However, he had no other determination for his 
fossils than that furnished by Gabb, which was not very critical and 
so we must rely on later work for the differentiation of the Jurassic. 
Tt will be seen later that the plants and invertebrates from the coal 
horizon of the Cordillera Occidental have been shown to be Creta- 
ceous. However, Raimondi in some instances was probably correct in 
assigning formations to the Jurassic, since it is now known to be pres- 
ent and has yielded numerous fossils. Bravo has called attention to 
the fact that Gottsche* has made mention of an ammonite from 
Morococha which is in the Freiburg collections. 
Fossil ammonites from Huallanca, in the Department of Ancachs, 
collected by Durfeldt and belonging to the Freiburg Museum, were 
studied by Steinmann (1881) and considered by him as indicating 
the Tithon (which is homotaxial with the Portlandian) and belong- 
ing in the upper part of the Jurassic. 
CRETACEOUS. 
The island of San Lorenzo at Callao was examined by Dana, and 
his description is published in the report of the Wilkes expedition 
(1849). He made some detailed sections of the rocks and found 
some fossils which he considered as indicating the oolitic. He refers 
in a footnote to the fact that James Delafield had reported® upon 
some fossils which Doctor Brinkerhoff had collected from the island 
and presented to the New York Lyceum of Natural History. Dela- 
field did not venture an opinion as to the age of the fossils. 
Doctor Pickering, who was with Dana, found an ammonite at the 
head of the Chancay Valley at an elevation of 15,000 feet in rocks 
similar to those of San Lorenzo Island. This specimen is described 
in the appendix of the report as Ammonites pickeringi. Some fos- 
sils from Trujillo are also figured. 
@Uber Jurassiche versteinerungen aus der Argentinische Cordillere. Dr. 
Carl Gottsche, Cassel, 1878. 
b Amer. Journ. Sci., Vol. 38, p. 201, 1839. 
