GEOLOGY OF PERU ADAMS. 397 



in Peru, since the localities are very near the border. D'Orbigny also 

 referred the rocks at Arica to the Carboniferous on very slight evi- 

 dence, but this has been refuted by Forbes. The writer " found fos- 

 sils at Arica, which, according to Bravo, are Cretaceous, although he 

 did not determine them specifically. 



The Carboniferous areas examined by Forbes (18G1) are on the 

 peninsula of Copacabana and the projecting headland opposite on 

 Lake Titicaca. On account of a declaration of war Forbes was placed 

 in a suspicious position, since these localities are on the frontier be- 

 tween Peru and Bolivia. He, however, obtained a collection of fossils 

 which were determined by Salter. Forbes states that the Carbonif- 

 erous is also to be found to the north of Lake Titicaca. 



The fossils collected by Agassiz (1876), together with some others, 

 were studied by Derby (1876), who described 9 Carboniferous spe- 

 cies from Yampata and the island of Titicaca. He also found a 

 Spirifer in materials brought by James Orton from the Pichis River, 

 and in his notes says that he has recognized Productus and Strepto- 

 rhynchus from near Mayobamba in northern Peru. Agassiz, in the 

 notes accompanying Derby's paper, states that specimens of Fusulina 

 were sent to Mr. Brady for identification. The notes as to the occur- 

 rence of the Carboniferous are by Agassiz, who says that near Lake 

 Titicaca it lies in a rather limited elongated basin, with the axis in a 

 northwest-southeast direction. He identified the Carboniferous at 

 Vilca, Santa Lucia, and Sumbay, and says that Mr. Orrego stated 

 that Carboniferous is found as far north as Caylloma, and quotes 

 Orton as saying that Raimondi reported he had traced the Carbonif- 

 erous series to a height of 1,400 feet on the Apurimac at a locality 

 intermediate between the Pichis River and Cuzco. It would seem to 

 the writer that until fossils are found the identification of the Car- 

 boniferous at the places mentioned by Agassiz, and especially those 

 reported by Mr. Orrego, should not be definitely referred to the 

 Carboniferous. The writer in journeying to Caylloma observed 

 sedimentary formations which appear to be Cretaceous. 



Balta (1899) reviewed the Carboniferous of Peru and published 

 a sketch map showing two areas in which the Carboniferous had been 

 shown to exist, namely, in the Titicaca basin and the locality from 

 which Orton's Carboniferous fossils were obtained. He added noth- 

 ing especially new. 



A small Carboniferous area was reported^ by Fuchs (1900) as 

 being found in the peninsula of Paracas, just south of Pisco, on the 

 Pacific coast. The formation there contains some thin coal which 



" See Boletin del Cuerpo de Ingenieros de Minas del Peru, No. 45. p. 19, 1906. 

 * Nota sobre el Terreno Carbonifero de la peninsula de Paracas, F. C. Fuchs, 

 Bol. de Minas, T. XVI, 1900. 



