24 bulletin: museum of comparative zoology. 



ground a few kilometers south of Corytibanos, frogs abounded in 

 small grassy swamps or lakelets. One frog had a weak peep, another 

 a rattling croak, and one a cry like that of a baby. The great number 

 of these small lakelets on the trap plateau with standing sweet water 

 even in the dry season of the year is evidence that the rock crevices are 

 well supplied with water. The occasional rains which we encountered 

 and the impervious nature of the deeper rock together with the 

 residual clays which form the bottoms of depressions unite to keep 

 much water in sight at the surface. Yet there is a great variation 

 in the amount of permanent moisture present in the soil in the several 

 habitats of plants, the quantity increasing from the hills towards the 

 narrow valley floors as is exemplified in the distribution of the tree- 

 ferns and the bamboos. We saw grass or forest fires yesterday and 

 today in distant broad valleys. 



Another puma was reported in sight by the men just as we retired. 

 The first snake which I have so far seen in Brazil, a small bright 

 graceful green snake, was encountered on one of the little bridges 

 south of Corytibanos. Araucaria continues to be the dominant 

 forest tree. With it and rivalling it in size is the scraggly imbuia 

 whose bole attains a diameter of 3 feet or about a meter. What 

 impressed me most concerning the trees of south Brazil was the 

 small ovate leaves with entire margins which so many of them pos- 

 sess. The broad leaved oaks, maples, tulip-trees and other forms 

 familiar to the North American as existing species with precursors 

 occurring fossil as far back as the Cretaceous are here wanting. So 

 far as leaf evolution goes these simple outlines recall the forms which 

 are so characteristic of primitive types in all organisms. 



On the north bank of the small stream on which we camped this 

 night there was exposed a bed of red shale traversed by small 

 vertical faults with downthrow in each case on the west. This 

 stream, the Lageado penteado, is a branch of the Rio Canoas. The 

 name Lageado applied to streams like that of Lages given to the town 

 to which we were bound has reference to the slabs of sandstones 

 which abound in this region and "pave" as it were the beds of the 

 small streams. 



The Canoas river has shifted its course in the degradation of the 

 region down the dip of the formations so as to hug the southern edge 

 of the basalt. 



I saw no fossils in the red shales but found some concentric con- 

 choidal fractures or joints. 



August 26th. — Light showers during the night. Ant-hills and 



