14 bulletin: museum of comparative zoology. 



conglomerates such as constitute the tilUte beds. Some of the coarse 

 gritty beds contained clay particles. In all probability these were 

 once grains of feldspar indicating that the unaltered rock was a 

 granitic sandstone related to arkose. Dikes or sills of basic intrusives 

 occasionally intersect the sandstone along this route. 



July 28th. — Through the courtesy of Dr. Cruz Lima we travelled 

 in a special car from Itarare to Jaguariahyva, stopping in the newly 

 opened railway cuts to examine the tillite beds. At the first stop in 

 a cut above the Rio Jaguaricatu in Parana a well-striated pebble was 

 found in a boulder-bed, establishing at once the identity of origin 

 of these deposits with those of India and South Africa. 



July 29ih. — Continued the journey by rail to Ponta Grossa, the 

 headquarters of the party engaged in the geological survey of Parana. 



The railway from Jaguariahyva to Ponta Grossa crosses the 

 Devonian sandstone cuesta affording a magnificent view of the 

 country. 



Between Pirahy and Coxambu the Pre-Devonian rocks, exposed 

 in a lowland widened out along the course of the Rio Yapo, comprise 

 a tilted group of rocks of which I have seen no account in the descrip- 

 tions of the metamorphosed district of the Serra do Mar. At Pirahy 

 Station there is a monoclinal set of beds in a ridge west of the railroad. 

 The beds strike north by east and dip about 30° west. About a 

 mile south of Pirahy at a water-tank a felsitic breccia crops out. 

 Farther south the train passes through a cut in which slightly meta- 

 morphosed shales, sandstones, and a pebble bed with fragments of 

 red felsite, granite, etc., appear, having a reddish color and dipping 

 westward at an angle of about 30 degrees. These rocks from their 

 relatively unmetamorphosed condition appear to be younger than the 

 belt of slates and limestones described as occurring in Sao Paulo. 

 No fossils were seen in the section nor did time permit a satisfactory 

 search for further details of the stratigraphy. This formation, so 

 different from the members of the Pre-Devonian terrane on the east, 

 is the most western member of the highly inclined rocks seen in Parana 

 and suggests that some horizon between the Middle Devonian and the 

 slate and limestone terrane may yet be worked out and correlated 

 in this field. 



Several days were spent at Ponta Grossa in the examination of the 

 surrounding country, including a visit to Conchas where a bed of 

 tillite is to be seen. In the Carboniferous sandstones west of Ponta 

 Grossa I found some worm burrows of the type known as Monocra- 

 terion; these show a cup-shaped superior termination and a vertical 



