l82 FLORIDA GEOLOGICAL SURVEY SIXTH ANNUAL REPORT. 



important soil renovators in clayey soils, especially in climates a 

 little cooler than ours, are rather scarce m Florida. Our two larg- 

 est burrowing animals, which are confined to the coastal plain, or 

 nearly so, and seem to be more abundant in Florida than in any 

 other state, are the "salamander" (a rodent, Gcumys TiLza)*- and the 

 "gopher' (a turtle, Testudo or Gopherus Polyphemus). These, 

 especially the former, are common in dry sandy pine lands, and to- 

 gether thev must move almost every particle of soil in considerable 

 areas every few years, and thus counteract to a considerable 

 extent the leaching effect of the rain. In places not accessible to 

 these animals, such as islands, the soils are often perceptibly poorer 

 than the average. Other common soil animals are moles, crawfish 

 (in wet places), crabs (in and near salt marshes), and many insects 

 and Crustacea which have not been identified. 



Climate. As the climate does not vary much from one point to 

 another within the area studied (which extends over less than two 

 degrees of latitude), it is not discussed for each region separately. 

 The following table gives certain climatic data which appear to be 

 significant, for all stations in northern Florida for which the records 

 have been kept long enough to make the averages reasonably accu- 

 rate. Most of them are taken from Section 83 jof Bulletin W of 

 the U. S. Weather Bureau, which brings the records down to the 

 end of 1908. 



The data selected are the average temperature for January, July, 

 and the whole year, in degrees Fahrenheit, the average length of the 

 growing season (period between last killing frost in spring and first 

 killing frost in fall), in days, the average annual rainfall, in inches, 

 and the percentage of it that comes in the four wannest months 

 (June to September) and in the six warmest months (May to 

 October, inclusive) . 



*For notes on the distribution and habitats of this animal in Florida and 

 elsewhere see Science II. 35:115-119. Jan. 19, 1912. 



