ON THE ZOOLOGICAL POSITION OF TEXAS. 7 



from the Gulf of Mexico. The region lying to the west of that meridian 

 receives winds which are generally depleted of their moisture before reach- 

 ing it. West winds, of course, lose their rain on the Sierra Madre of 

 Mexico ; southwest winds come over the arid plains of the plateau, while 

 south winds come direct from no sea, and have generally left their watery 

 freight on the hills and forests of Eastern Mexico. Hence Western Texas 

 is related to the east, as Colorado is to Missouri, hut here in the south, 

 these regions are brought into juxtaposition without a wide inter^'al of 

 plains. 



Eastern Texas is, up to the eastern boundary of the Lignitic belt, forest 

 covered. In the wet regions are the usual cypress [Taxodium) swamps; 

 in the loamy soils the live-oak and hackberry (CeUis) forests, and on the 

 sandy uplands the pine; all more or less draped with the Tillandsia, 

 when within reach of the daily breezes from the ocean. Between the 

 western boundary of the forests and the first steppe of limestone is a 

 great tract of plains. From the Eed Eiver to Houston and west to Aus; 

 tin one great prairie extends, intermitted here and there by patches of 

 post-oak and black-jack [Quercus obtusiloba and Q. nigra). Southward it 

 is diversified by swamps, with or without Taxodiun, and alive with flocks 

 of water-fowl. Here also, following the trend of the coast on the one 

 hand and the lines of elevation on the other, the prairie region turns to 

 the westward, extending to San Antonio and beyond. This southern 

 portion of it is much interrupted by live-oak forest and mesquite open- 

 ings along its northern border. This prairie region differs from the great 

 l^lains of the Xortli in. not being covered by the buffalo-grass, but in 

 supporting longer and coarser species. The region of the first plateau, 

 as the hill country west and north of the plains may be definitely called, 

 is not forest covered, nor is it naked. The highlands are diversified 

 with numerous patches of dense shrubbery or brush, with growths of 

 open timber of oak, and with grass. The hill-sides support the same veg- 

 etation, often of larger size, while the creek, river, and canyon bottoms 

 are filled with dense forest. The principal trees are the pecan {Gary a 

 olivaformis), button wood {Plaianus occidentaUs), hackberry {Celtis occi- 

 dentalis), pin-oak (Quercus palustris), and live-oak {Quercus virens)', an 

 ash {Fraximis), elm {Ulmus crassifoUa), wild china {Sapindus marcjina- 

 tus), and a spinous barberry with three leaflets. The brush includes 

 many species of much interest to the botanist. Especially is the north- 

 ern observer struck with the great number of leguminous plants on the 

 lower levels, as mesquite {Algarohia glandulosa), tlie Acacia famesiana, 



