288 E. H. SELLARDS 



through to permanent water level, thus forming small circular lakes. 

 In the lake region the calcareous rocks are covered to a greater 

 depth. The lakes are usually circular in outline and are deep, with 

 high banks. In extreme western Florida, including Escambia and 

 Santa Rosa counties, the calcareous deposits are buried beneath 

 the surface to such a depth as not to affect the topography. A 

 similar region is found on the east bank of the Apalachicola*River, 

 including Gadsden and the northern part of Liberty counties. 

 Under these conditions the topogtaphy is determined by the normal 

 drainage courses. 



CLIMATE, TEMPERATURE, AND RAINFALL 



The climatic conditions of the state are appreciably influenced 

 by the proximity to oceanic waters. This is especially noticeable 

 with regard to temperature, rainfall, and humidity. The tempera- 

 ture is moderate, the rainfall moderately heavy, and the humidity 

 high. The mean annual temperature near the northern line of 

 Florida is about 67° F., while at Key West in extreme southern 

 Florida the mean annual temperature is close to 77° F. By far the 

 greater part of the state lies within an area which receives between 

 48 and 57 inches annual rainfall. In extreme southern Florida on 

 the Keys is a small area in which the rainfall is much less, the 

 average for the station at Key West being about 38 inches. On the 

 other hand a small area in extreme western Florida and another 

 along the South Atlantic Coast receives an annual rainfall approxi- 

 mating 60 inches. The average annual rainfall for the state as a 

 whole is close to 54 inches. The rainfall is distributed irregularly 

 throughout the year. The driest months are April and November, 

 while the heaviest rainfall comes as a rule from June to September. 

 Variation in rainfall is pronounced in Florida. This variation is 

 due in part to normal seasonal variations, and in part to the influ- 

 ence of heavy tropical storms, especially those of the late summer 

 and fall. These storms, or hurricanes, which fortunately are not 

 of frequent occurrence, usually result in a heavy precipitation in the 

 belt of country through which they pass. 



The maximum recorded precipitation for one year in Florida is 

 probably that of 191 2, at which time the rainfall for the state was 



