1885.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 475 



from the river; it now forms a tolerably well defined wooded belt which 

 runs parallel with the river to its mouth and spreads north of it from 

 20 to 40 miles. 



Laredo stands on a broad and level sandy plain over which it has been 

 projected to convey the waters of the Rio Grande. Mezquit continues 

 to be the prevalent shrub ; the Huisache ( Acacia Farnesiana) and Re- 

 tama (Parkimonia aculeata) are much more common; the Colima (Xan- 

 thoxylum Pterota) begins to appear. In gardens and yards are noticed 

 the elegant Tobacco- Shrub (Xicotiana glauca) of arborescent size, and 

 the Mexican Maguey [Agave Americana). The river shore is mostly 

 bare; at intervals are clumps of Black Willow, Hackberry, Water Elm 

 ( Ulmus crassifolia), and Texas Green Ash (Fraxinus viridis, var. Per- 

 landieriana). Along the water's edge was collected a genus of Grass 

 (Hemarthria) new to the United States. 



Proceeding on the narrow-gauged railroad toward Corpus Christi, 

 one crosses the undulating, hilly wooded belt, the shrubs being: Mez- 

 quit, Huisache, Granjeno, Hackberry, Texas Persimmon, Parlcinsonia 

 aculeata and Texana, Condalia obovata and Mexicana, Acacia amentacea 

 and Wrightii, Kancinskia. Here also begin to be seen, in the wild 

 state, rare patches of Maguey (Agave Americana), which, as a native 

 pla nt, grows very sparsely on the Texas side of the Lower Rio Grande. 

 The Nopal (mostly Opuntia Fngelmanni), of very thrifty growth, is every 

 where abundant in the woods which it sometimes renders impassable. 



Opposite Belleville, the Salado, one of the largest rivers of Northern 

 Mexico, flows into the Rio Grande. At the time of the Boundary Sur- 

 vey* Cypress (Taxodium distichum) was rather common on its shores and 

 extended down the Rio Grande to Roma. It is quite sparse now but 

 is occasionally noticed as far down as Edinburg. At Havana Ranch I 

 saw a fine specimen of this tree 2 feet in diameter. 



Below Belleville, bluffs and high mesas gradually recede while the 

 valley widens; much of it now is susceptible of cultivation. Roma is 

 the head of high-water navigation, while Rio Grande City is generally 

 reached by steamers at all stages of water. 



At Rio Grande City (Ringgold), the woody vegetation on the neighbor- 

 ing bluffs and throughout the river belt, 30 miles or more wide, is dense, 

 and in low places reaches the magnitude of scrub timber. The natute 

 of it has changed; one now commonly sees: Nacahuite (CordiaPoissieri), 

 a small tree with large, mulberry- like leaves and excellent fruit ; Bar- 

 retta (Eelietta parvifolia), which, although a common shrub here, had 

 not before been observed in the United States; Ebony (Acacia flexi- 

 caulis), an evergreen shrub or small round-headed tree 1 foot in diame- 

 ter; Colima (Xanthoxylum Pterota), spiny shrub with pungent leaves; 

 more rarely Ptelea angustifolia. The other shrubs also growing in this 

 locality have already been noticed. They are Mezquit, Texas Persim- 

 mon (Chapote of the Mexicans), Granjeno, Guayacan, Junco, of arbor- 



