INTRODUCTION. 
The State of Texas, an empire in itself, comprising one-twelfth of the 
area of the United States, with great diversity of soil and climate, must 
necessarily present a corresponding diversity in plant life. When all of 
its immense area is thoroughly explored it will undoubtedly yield as 
many or perhaps more species than are contained within the limits of 
Gray’s Manual. 
As is stated in the Introduction to the Botany of the Mexican Bound¬ 
ary Survey, a line drawn from the Pan Handle southeast to the vicinity 
of Corpus Christi divides the State into two unequal portions. The 
smaller eastern part is well watered as a whole, and gives rise to more 
luxuriant vegetation than the other, where rain is uncertain and often 
scanty. The flora of this eastern section, at least in its northern and 
eastern portions, has many species in common with the adjacent States 
of Louisiana and Arkansas and the Indian Territory. 
In the Contributions from the U. S. National Herbarium, “Upon a 
Collection of Plants made by Mr. G. C. Neally, in the Region of the 
Rio Grande in Texas, from Brazos Santiago to El Paso County,” sixty- 
four species of Cyperaceae are mentioned. Four of these have no 
station assigned, while forty-seven were collected about Sabine Pass in 
extreme eastern Texas, near the mouth of the Sabine river. As the 
plants of this order are usually frequenters of places where there is an 
abundance of moisture, we have a very good index to the character of 
the country where they are found. 
The larger southern and western division, in many places a veritable 
desert, contains many peculiar plants, found only within its areas, es¬ 
pecially in the central portions, in the limestone foothills, and in the 
mountains of the extreme western part. Along the southern border the 
species are essentially Mexican, intermingling in the mountain region 
with more northern forms found in the mountains of New Mexico and 
