90 THE ISTHMUS OF PANAMA. 



and as to the lower creations, they certainly abound 

 in the greatest number and variety. 



The latitude of that part of the Isthmus over 

 which the Panama Railroad passes, is between 8 

 and 9 degrees north, and consequently is subjected 

 twice in the year to the vertical rays of the sun, viz. : 

 about the 21st of April and near the middle of Au- 

 gust. The year is divided into two seasons, with little 

 e]se to distinguish them than that the one is wet, and 

 the other dry, and in this they are strongly marked. 

 The rainy season is their winter, and corresponds 

 with our summer, the rains beginning to fall about 

 the first of May, usually, and terminate in Decem- 

 ber; and thus, although this is their coolest season, 

 in consequence of the heavy rains and evaporation, 

 yet it is also the period when the sun's rays fall most 

 vertically ; and therefore the two great elements in 

 the production of unhealthy exhalations, viz. : heat 

 and moisture, are operating in their extremest degree 

 at the same time. But it should be understood that 

 it is while the surface is undergoing the change from 

 wet to drv, that miasma is eliminated most rap- 

 idly. 



During the first two or three months of the wet 

 season, it does not rain more than is generally found 

 agreeable for comfort, and to advance the growth 

 of vegetation ; and about the 21st of June it clears 

 up, and probably not a drop of rain will fall for a 

 w T eek. This season is called by the natives El Ve- 

 ranito di San Juan. (Little summer of St. John.) 

 Now, during this period, the earth is alternately 



