I eee eee eee eee neared ietdiadedhtemdntarinunt nett vtigen re eer ar i EE 
36 
the map will show. His plants partake, therefore, of the cha- 
racter of the Floras of the widely different countries which are 
separated by this valley. Indeed, the Flora of the valley of the 
Rio Grande connects the United States, the Californian, the 
Mexican, and the Texan Floras, including species or genera, or 
families, peculiar to each of these countries. 
The north-eastern portion of the route traverses the large 
western prairies, rising gradually from about 1,000 feet above 
the gulf of Mexico, near Independence, Missouri, to 4,000 feet 
west of the Cimarron river. The plants collected on the first 
part of this section, as far west as the crossings of the Arkansas 
river, are those well known as the inhabitants of our western 
plains. I mention among others, as peculiarly interesting to 
the botanist, or distinguished by giving a character to the lands- 
cape, in the order in which they were collected, Zradescantia virgi- 
nica, Phlox aristata, Gnothera missouriensis, serrulata, speciosa, 
&e., Pentstemon Cobaa, Astragalus caryocarpus, (common as far 
west as Santa Fe,) Delphinium azureum, Baptisia australis, 
Malva Papaver, Schrankia uncinata and angustata, Echinacea 
angustifolia, Aplopappus spinulosus, Gaura coccinea, Sida coccinea, 
Sophora sericea, Sesleria dactyloides, Hordeum pusillum, Eingel- 
mannia pinnatifida, Pyrrhopappus grandiflorus, Gaillardia pul- 
chella,* Argemone Mexicana (with very hispid stem and large 
flowers). 
The plants collected between the Arkansas and Cimarron 
rivers are rarer, some of them known to us only through Dr. 
James, who accompanied Long’s expedition to those regions In 
1820. We find here Cosmidiwm gracile, Torr. and Gr., which 
has also been collected about Santa Fe and farther down the 
Rio Grande; Cucumis ? perennis, James, found also near Santa 
Fe and about Chihuahua, and by Mr. Lindheimer in Texas; 
the petals being united about two-thirds of their length, it 
cannot be retained under the genus Cucumis; Hoffmannseggia 
Jamesii, T. and G., was also gathered on this part of the journey ; 
several species of Psoralea, Petalostemon and Astragalus; also 
Torry’s Gaura villosa, and Krameria lanceolata; Krysimum 
asperum, which before was not known to grow so far south; 
Polygala alba, Lygodesmia juncea. Were we also, for the first 
time, meet with Rhus trilobata, Nutt., which, farther west, becomes 
a very common plant.t A new Zalinum, which I have named 
* Abundant in the sands about the Arkansas river, with beautiful flowers, 
but only about six inches high ; certainly annual. 
+ Like many other plants mentioned here, it has been collected in abundant 
and beautiful specimens by Mr. 4. Fendler, a young German collector, who has 
~~ ~~ Pre 
