Apr., 1921] 
HANSON MALVACEAE IN TEXAS 
A. Humid Section 
Topography: Usually low and flat with occasional low hills. Drainage 
is poor, so there is much marshy land. Adjacent to the coast is a strip of 
salt marsh, often several miles wide. Soil: Black clay chiefly. ■ Elevation: 
Most of the area is below 100 feet; Beaumont 29 feet, Galveston 9 feet. 
Rainfall: The annual mean in the eastern part is over 50 inches and in 
Fig. I. Map of Texas, showing life-zones. I. Semi-tropical Gulf Strip: A. Humid 
Section, B. Xerophytic Section. II. Austroriparian. III. Lower Sonoran: A. Rio 
Grande Plain, B. Great Plains, C. Plateaus and mountains below 4000 feet. IV. Upper 
Sonoran: A. Great Plains, B. Plateaus and mountains above 4000 feet. 
the western part about 35 inches; at Beaumont, 45.1 inches; at Galveston, 
47.6 inches. Temperature: The mean annual temperature at Beaumont is 
68° F., at Galveston 69.4° F. Clear Days: The percentage of clear days in 
1918 at Beaumont was 38.8, at Galveston 28.8. Humidity: Very high, 
as is indicated by the abundance of Spanish moss {Tillandsia spp.) on trees. 
Most of this section is open prairie characterized by such genera as 
Rudbeckia, Oenothera, Sabbatia, Panicum, Baptisia, Eragrostis, Andropo- 
gon, and others. From the east the Atlantic type of woodland is invading. 
