xiv CONTENTS 



10. Mississippi. GLADYS HOKB, Converse College 454 



11. Louisiana. G. W. GOLDSMITH, Carnegie Institution, LENTHALL 



WYMAN, United States Forest Service, and H. H. KOPMAN, 

 Louisiana Department of Conservation 460 



12. Arkansas. JOHN T. BUCHHOLZ, University of Arkansas 464 



Texas. (See page 502.) 



D. States Chiefly Oak Grove Savanna 469 



1. Illinois. T. H. FRISON and R. B. MILLER, Illinois Natural 



History Survey 469 



2. Iowa. L. H. PAMMEL, Iowa State College 480 



3. Missouri. A. C. BURRILL, Missouri Resources Museum 485 



4. Oklahoma. H. H. LANE, University of Kansas 490 



Texas. (See page 502.) 



E. States Chiefly Grassland or Steppe 502 



1. Texas. A. R. CAHN, University of Illinois 502 



2. Kansas. J. W. McCoLLOCH, Kansas State Agricultural College. 515 



3. Nebraska. R. H. WOLCOTT, University of Nebraska 519 



4. Colorado. F. RAMALEY and W. W. ROBBINS, University of 



Colorado 524 



5. Wyoming. JOHN W. SCOTT, University of Wyoming 529 



6. Montana. M. J. ELROD, University of Montana 537 



7. North Dakota. J. T. SARVIS, United States Bureau of Plant 



Industry, and J. E. SWITZER, Indiana University 544 



8. South Dakota. E. J. PETRY, South Dakota State College, and 



S. S. VISHER, Indiana University 548 



F. States Chiefly Desert and Semi-Desert 556 



Oregon. (See under Coniferous Forest.) 

 California. (See under Coniferous Forest.) 



1. Utah. C. F. KORSTIAN, United States Forest Service 557 



2. Nevada. C. F. KORSTIAN, U. S. Forest Service 560 



3. Arizona. G. A. PEARSON, U. S. Forest Service, E. A. GOLDMAN, 



United States Biological Survey, FORREST SHREVE, Carnegie 

 Institution, and CHARLES T. Vorhies, University of Arizona 562 



4. New Mexico. A. O. WEESE, University of Oklahoma 570 



Section 8. The Tropics North of the Equator 574 



A. Mexico and Central America 574 



1. Mexico. E. W. NELSON and E. A. GOLDMAN, United States 



Biological Survey 574 



2. Guatemala. WILSON POPENOE, United States Department of 



Agriculture 596 



3. British Honduras. KARL P. SCHMIDT, Field Museum 600 



4. Honduras. KARL P. SCHMIDT, Field Museum 601 



5. The Republic of Salvador. PAUL C. STANDLEY, U. S. National 



Museum 602 



6. Nicaragua. LUDLOW GRISCOM, American Museum of Natural 



History 604 



7. Costa Rica. LUDLOW GRISCOM, American Museum of Natural 



History 607 



8. Panama. E. A. GOLDMAN, United States Biological Survey, and 



JAMES ZETEK, Custodian of the Barro Colorado Island Labo- 

 ratory, United States Bureau of Entomology 612 



B. Northern South America 623 



1. Colombia. FRANCIS W. PENNELL, Academy of Natural Sciences 



of Philadelphia .623 



