206 



AMAZONIA AND LA PLATA. 



channel, althougli its outer margin facing seawards coincides exactly with the 

 normal coast-line. Similar conditions are presented by the granite island of Santa 



Fig. 86. — S. Sebastiao and its Island. 

 Scale 1 ; 500,000. 



45° 50- 



West or breenwich 



45°i0' 



0to5 

 Fathoms. 



5 to 10 

 Fathoms. 



Tepths. 



10 to 25 

 Fathoms. 



25 Fathoms 

 and upwards 



12Milps. 



Catharina, which an upheaval of eight or ten feet would suffice to connect with the 

 mainland by a narrow stem projecting between the northern and southern inlets. 



Parana Hyurogkaphic System. 



To the somewhat precipitous slope facing the Atlantic corresponds the long 

 gentle incline stretching inland towards the Rio Parana. One section of this 



