62 bulletin: museum of comparative zoology. 



to have been found in place; but the tree trunks cannot be far out of 

 position, and the general character of the section points to the sub- 

 aerial accumulation of certain of the sandstones in the manner of 

 outwash plains such as now accumulate in front of glaciers or in 

 similar situations permitting the growth and fall of trees between 

 times of aggradation by debris-laden streams. Only a detailed survey 

 of the region would suffice to determine more definitely the relations 

 to sea-level and the existence of lenses of tillite in the section. 



Tillite Beds on the Rio Jaguaricatu in Parana.. Sengens is a station 

 on the newly constructed line of railway from Itarare to Jaguariahyva 

 in northeastern Parana, on the south bank of the Rio Jaguaricatu. 

 In the railway cuts which were fresh in 1908 good sections of the 

 glacial boulder-clays or tillite were exposed for several kilometers in 

 either direction. The Station is near the 228 kilometer post. The 

 foIloAving notes pertain to the exposures along the curving course of 

 the railroad which follows down the right bank of the river towards 

 Sao Pedro de Itarare. Near post 234 a well-striated sandstone pebble 

 was found dislodged from a sandy conglomerate or tillite at this 

 locality. This pebble is shown in Plate 21 to the left of the 

 hammers. The striated surface is well flattened and the edges 

 battered off. It displays no zigzag striae and may be a fragment of 

 the old glaciated floor. Somewhat farther to the northeast between 

 posts 234 and 235 the boulder-clay type of tillite is well shown, as in 

 Plate 21, there containing small boulders of granite. 



Between posts 235 and 236 apparently near the top of the local 

 bed the view shown in Plate 22 was taken. At this point in a 

 fresh railway cut there is exposed an angular slab-like block of a fine 

 grained white sandstone resembling novaculite, nine feet (three 

 meters) long and about twenty-one inches thick, the third dimension 

 not being ascertainable, the largest angular block I myself saw in any 

 section in Brazil. This rock is practically identical, lithologically, 

 with a white sandstone layer which occurs lower in the section at a 

 locality along the railway where a fault brings the beds towards the 

 surface. (Fig. 13). 



This fault extends in a northwest direction and the downthrow 

 appears to be towards the west. The sandstone in question is here 

 overlaid by pebble beds. Between these eastern exposures and 

 Sengens there are coarse sandstones containing at least one pebble 

 bed with a greater proportion of granitic pebbles than are found in the 

 more typical tillite of the district. From this pebble bed I collected 

 three stones carrying faint striae. 



