242 PROCEEDINGS OF THE NATIONAL MUSEUM vol. io9 



eastern portion of the Isthmus of Darien adjacent to the South 

 American Republic of Colombia (fig. 1). Panama is about 400 miles 

 long from east to west, and its width varies from less than 50 miles at 

 the Canal to about 125 miles at the Azuero Peninsula east of the 

 Canal Zone. The northern, or Atlantic, coast forms a flattened S- 

 shaped curve, undented except for the Chiriqui Lagoon at the west. 

 The southern, or Pacific, coast line is very irregular, with several 

 peninsulas and bays, the eastern part forming an arc around the 

 Gulf of Panama. A number of islands lie off the coasts. Panama 

 has an area of over 34,000 square miles and ranges in altitude from 

 sea level to 11,500 feet in the Volcan region near the Costa Rican 

 border. A number of mountain ranges form the backbone of the 

 Isthmus of Panama, with low passes between, the lower ones located 

 toward the central part of the country at the Canal Zone. From 

 west to east the principal mountain ranges arc the Volcan de Chiriqui 

 (11,500 feet) and the Serrainia Tabasard (9,200 feet) west of the 

 Canal Zone and the Cordillera de San Bias (2,900 feet) and the Ser- 

 rainia del Darien (7,500 feet) closely bordering the Atlantic coast to 

 the east. The upper slopes of the mountains are steep but not 

 precipitous, gradually merging into hilly country below with numer- 

 ous narrow river valleys separated by narrow, greatly eroded ridges. 

 Extensive plains are found at various elevations in Chiriqui Province 

 and on the Pacific coast from Chepo west to the Canal Zone. The 

 larger rivers flow into the Pacific, the principal ones being the Tuira- 

 Chucunaque in Darien Province and the Chepo-Bayano in Panamd 

 Province; the Chagres River drains a wide area near the Canal Zone 

 and originally flowed into the Atlantic, but now is impounded in 

 Madden and Gatiin Lakes and flows through the locks of the Panama 

 Canal into both oceans. 



Climate (Goldman, 1920; Kenoyer, 1929; Arnett, 1950): Lying 

 between the latitudes of 5° and 10° North, the Republic of Panama 

 has a tropical climate in the strict sense, with temperatures at sea 

 level the year around of about 90° F. during the day and 70° F. at 

 night. Temperature varies with altitude, and thus some of the 

 higher mountains are temperate. The annual cycle is made up of 

 two seasons, the wet and the dry. During the wet season, from 

 May to December, the prevailing wind is from the south, and rains 

 are frequent and widespread throughout the country. During the 

 dry season, from December to May, the prevailing wind shifts to the 

 north, and while the northern slope of the country receives frequent 

 light rains, the southern slope lying in the rain shadow of the mountains 

 receives very little precipitation. 



