434 Scientific Notices. 
trees grow along them. They are mostly stunted specimens of the Post-Oak, 
the Rock Chestnut Nira oe Persimmon, the Mockernut, the Juniper, and a 
a, Pers, T 
shrub, Bumelia lan ers. e characteristic 1 herbaceous plants o 
sis ‘limestone prairi ae Gye ially: Ambrosia polystachya, Kuhnia Eupa- 
rioides, Aster haitan Croton cayitatum, Grindelia aeesteie Pda “yee 
Getbaphcs us albidus, &c., species which are not found on the prairies of o 
formation. Besides these plants ney are covered with a great number of 
pecies belonging to the prairies in general. 
Between this and the second iain of the prairies, viz., of those which 
are formed on the Carboniferous shales and ony, there is a remarkable transi- 
tion, which unites both divisions, Se er shows their common origin. In the 
western parts of Benton and the northern RN t of Washington counties some 
or red clay, have still at their surface some isolated patches of Subcarbonifer- 
ous chert rty ti ‘lin mestone, which appear here and there, preg the ere hori- 
zontality like small mounds, Possibly these low moun ould support the 
vegetation of the ee, and they may live i Ro a into oes by 
the influence of fire, which is a secondary agent of their formation. But the 
soil which covers them is exactly of the same nature as the soil of the sur- 
itges J prairies, and as their height is no more than two or three feet, they 
may have been formed in the same manner and by the agency of water. 
rairies on the Carboniferous shales are generally flat, surrounded by 
higher border, which gives them the appearance of the 
u 
ri ne 
marshes for . ie and have the vegetation of marshes: the rushes and the 
ges mi-aquatic Spinel gives, sceonting to the nature of the 
underlying errata, either a hard, compact, cold soil, gat mposition of shales 
clay ; or, when mixed with i the peaty black ail of the prairies of IIh- 
Soin me of the Northern States. In the summer months, these marshy pause 
es. 
she prairie are more sterile or rather more difficult to cultivate than those 
of ection, as we shall have occasion to see when examining the 
counties S Sebastian samanue , &c., where this kind of prairie is mostly found. 
A few t er Oak, ‘the Pin Oak, the Honey Locust,—grow along 
the crenks: which Gena. in ‘their middle. The -soil is, in its natural state, 
mostly covered with the great Composite of the prairies and the hard grasses, 
species of Beard-grass and Broom-c 
The prairies of the third class are extensively formed in Arkansas on the 
Tertiary or Alluvial land bordering some rivers of the South, especially Red 
the other sections. From the cecene of Mr. Nut- 
tall, who oe these plains, their plants appear so — pee) from 
those other prairies. They rather bear the characte a Western 
Flora, or of the Flora of the plains extending toward Mex 
Then the geological nature of the soil, and the sani characteristics 
of the vegetation, the agricultural capabilities, &e., of different ees 
of the State are considered in n succession, and lastly, there is a catalogue 
of the plants of Arkansas, as far as known, systematically arranged, their 
Latin names, their English names, Geological station, and natural hab- 
eae ee 
