NATURAL AiiEAS AND REGIONS 



615 



Coulter, J. M. Botany of West Texas. 

 Contr. U. S. Nat. Herb. 11. 18'.)1- 

 1894. 



Hill, R. T. Physical Geography of the 

 Texas Region. ... U. S. Geol. Surv. 

 Top. Atlas of the U. S. 1900. 



Evermann & Kendall: The Fishes of 

 Texas. Bull. U. S. Fish Comm. for 

 1892. Washington, 1894. 



Small, J. K. Flora of the Southeastern 

 United States. 1903. 



Lewis, I. M. The Trees of Texas. Bull. 

 Univ. Te.xas No. 22. 1915. 



Rlearns, E. A. Mammals of the Mexican 

 Boundary of the United States. 

 U. S. Nat. Mus. Bull. 5G. 1907. 



Winkler, C. H. The Botany of Texas. 

 Bull. Univ. Texas. No. 18. 1915. 

 (Complete bibliography of Texas 

 botany to date.) 



Singley, J. A. Texas jMoUusca. A Pre- 

 liminary List of the Land, Fresh 

 Water, and Marine Mollusca of 

 Texas. Geol. Survey Texas, Con- 

 tributions to the Natural History of 

 Texas, Fourth Ann. Rep., 1892, 

 pp. 299-343. 

 Strecker, J. K. Reptiles and Am- 

 phibians of Texas. Bull. Baylor 

 Univ., Vol. 18, No. 4. 1915. 

 The Birds of Texas. Bull. Baylor 

 Univ. 



2. KANSAS 

 By J. W. McCoLLOCH 



I. OKIGIXAL BIOTA AND GEXEllAL 

 CONDITIONS 



1. Topography 



Three physiographic regions (fig. D 

 are recognized in the state: (1) the 

 Ozark uplift in the extreme southeastern 

 corner, (2) the Prairie plains comprising 

 the eastern one third, and (3) the Great 

 Plains which include the remainder of 

 the state. The transition to the latter 

 is gradual. The entire state is practi- 

 cally an undulating plain which slopes 

 gently from east to west at an average 

 rise of about 7 ft. per mi. There is a 

 difference of 3175 ft. in the altitude, 

 the lowest being 725 ft. in Montgomery 

 County and the highest 3900 ft. in 

 Wallace County. The gently rolling 

 prairies are diversified by an endless 

 succession of broad, level plains, isolated 

 hills and ridges and moderate valleys. 



Much of the difTcrcncc in the topoRraphy 

 is due to erosion und wind action. 



2. Climate 



The climate of KunBoa is typically 

 continental, being characterized by wide 

 extremes of temperature, great varia- 

 tions in the .seasonal rainfall, niurh 

 sunshine, and dry, bracing air, with 

 good wind movement. The tenipcrattire 

 of the various sections of the state is 

 fairly uniform, the average tcnifwrature 

 ranging from 58° in the southeastern 

 counties to 51° in the northwest, with a 

 mean of 54° for the state as a whole. 

 The highest temperature recorded is 

 110° and the lowest -40°. 



The distribution of the rainfall over 

 the state and the time of its occurrence 

 are the chief limiting factors. Precipi- 

 tation decreases with remarkable regu- 

 larity from 42 in the southeastern 

 counties to 15 on the Colorado line 

 (fig. 1). From 71 to 78% of this amount 

 falls during the growing months— April 

 to September. Droughts frequently oc- 

 cur, usually during July and August, 

 due to the high rate of evaporation 

 caused by the excessive amount of 

 sunshine and hot, dry winds. 



There is also a great difference in the 

 velocity of the wind in the various parts 

 of the state. In the eastern part the 

 winds are not noticeably higher than 

 those of the states to the cast, while 

 the western third of Kansas is one of 

 the windiest inland localities in the 

 country. Excessive evaporation occurs 

 in the western half of the state. M 

 Hays, the evaporation from an oi>en 

 tank during the six growing month.s was 

 45 and at Garden City it was nearly CO. 



5. Fauna and flora 



Mammals in the hardwood forests of 

 the valleys in the eastern part of the 

 state were found— such mammals as the 

 opossum {Didclphis virginiana), short- 

 tailed shrew (lilarirui brevicaiida), Mis- 

 souri Valley mole {Scahpus aquaticua 

 viachrinoidcs), timber wolf {Canis sp.), 

 coyote (Canis lalrans), red fox O'ulpca 



