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vegetation become intensely heated by the sun, and generate hot 
winds which scorch the grain fields. On most days from July 4 to 
August 24 the thermometer records at noon 90° F,, or at times 100° 
and even higher. The highest temperature recorded at Thedford was 
112° in 1830 and 113° in 1892, The mean temperature there for those 
two years was 78.4° and 80.2° for June, and 82° and 81° for July. 
The prevailing wind during the summer was from the southeast. 
From Professor Swezey’s report this appears to have been the case 
during the year 1892 also, The most rain came from northwest, the 
clouds going against the wind. In most cases, however, the wind 
changed during the heaviest shower, both wind and cloud then coming 
from northwest. From June 13 to August 10 we had at least one rainy 
day each week, but after that time the showers were few. In the night 
between August 2 and 3, a heavy dew fell as before mentioned, and a 
less heavy one the next night. These were the only times any dew 
was noticed during my stay. 
FLORA. 
I have described five districts, the first two of which, the Middle Loup 
and the Dismal River, are really branches of one. Their vegetation is 
nearly uniform, and is also similar to that of the wet-valley district, but 
with the addition of some castern plants which have ascended the river 
valleys. The plants of these three regions may be divided into four 
classes: (1) Sand-hill plants; (2) dry-valley or hillside plants; (3) 
wet-valley plants; (4) aquatic plants. In the fourth floral region dis- 
trict, the dry-valley region, the last two classes are lacking, and in the 
third, the barren sand hill region, plants of the first class only are found. 
SAND-HILL VEGETATION. 
The most characteristic plants of the sand hills are of course the 
four blowout grasses mentioned above, viz: Calamovilfa longifolia, Era- 
grostis tenuis, Redfieldia flexuosa, and Muhlenbergia pungens, of which 
the first two are also found on nearly every sand hill. Next to these 
four the following are the most common or the most characteristic 
herbaceous plants: 
Andropogon seoparius. Acerates viridiflora. 
Andropogon hallii. Acerates angustifolia. 
Stipa spartea, Acerates lanuginosa. 
Stipa comata. Astragalus ceramicus longifolius, 
Psoralea lanceolata. 
Psoralea digitata. 
Carduus plattensis. 
Opuntia rafinesquii. 
Euphorbia petaloidea. 
Kuphorbia geyeri. 
Chrysopsis villosa. 
Cristatella jamesii. 
Corispermum hyssopifolium. 
Croton tecensis. 
Commelina virginica. 
Tradescantia virginiana. 
Yucea glauca. 
Amaranthus torreyi. 
Frolichia floridana, 
Cyperus schweinitzii, 
Lacinaria squarrosa, 
Cycloloma atriplicifolia, 
Argemone albiflora, 
