72 bulletin: museum of comparative zoology. 



which a conglomerate 1.80 meters thick is recorded as resting on the 

 granite floor (White, loc. cit., p. 43). Eighteen kilometers south- 

 ward from Xarf[iieadas in another boring the Orleans conglomerate is 

 reported with large blocks of granite and Avith a thickness of 16.16 

 meters, resting directly on the granite. 



In the exposures reported between Florianopolis and Lages and 



•i i UoNorlel '^ / 



Fig. 20. — Section of the Minas-Orleans basin. • 



between Lages and Blumenau in Santa Catharina, there is described 

 among the beds beneath the conglomerate horizon " a very hard fine 

 grained grayish white whetstone grit" in layers eight to twenty 

 centimeters in thickness. These layers it is also stated gave the name 

 Navalha to the village on the Blumenau-Lages road near which 

 locality they were once quarried for whetstones. Similar beds are 

 likewise mentioned in the same report as resting with a few meters 

 thickness on the granite near Suspiro in Rio Grande do Sul and also 

 along the Rio Trombudo where crossed by the Blumenau-Lages road. 

 Attention may here be called to the fine-grained compact white sili- 

 ceous rock which underlies the boulder-beds on the right hand bank 

 of the Jaguaricatu along the railroad between Sengens and Sao Pedro 

 de Itarare in northeastern Parana described on page 62; fragments 

 of this rock appear to be abundantly distributed in the shales and 

 sandstone of Sao Paulo often with glacial scratches. 



I have little more than details of structure and the conclusions 

 based thereon to add to Dr. White's account of the Permian con- 

 glomerates of the Orleans basin. This basin (Fig. 21) is a down- 

 faulted outlier of the Permian area. The boundary fault, on the 

 western margin of the basin, brings the sediments against a basic dike 

 whose shattered condition suggests that the faulting occurred after 

 the intrusion of the dike. A short distance west of this broad dike 

 is a narrow basic dike somewhat faulted within its mass. I observed 

 two nearly vertical slickensided surfaces striking nearly northwest 

 southeast on which the shckensides pitch to the southeast on the 

 eastern fault at angles between twenty-fiAC and thirty degrees and 



