THE AMERICAN BOTANIST 143 



able what a wealth of vegetation was growing in the thin 

 layer of soil on the older exposures. Probably the rock be- 

 neath assists in sub-irrigation whenever surface water is 

 available, and this was a rainy period. 



Central Nebraska seemed to be the region where there 

 was a distinct change in the landscape. At Lincoln the 

 catalpa trees {Catalfya sf>c'ciosa) were in full bh^om. A small 

 one at Fargo had just begun to expand its leaf buds (flowers 

 (^n it opened July 9). Leaving Lincoln, Coniiis altcrnifolia 

 in flower became a conspicuous part of the landscape, re- 

 [)lacing our Viburniun of the north. Psuralca floribunda was 

 prominent on the prairie. The tall s[)iderwort (Tradcscaiitia 

 rcflcxa) displayed handsome masses of its blue flowers in 

 [)laces along the roadside. The flowers of elderberry (Sam- 

 bit ens canadensis) were beginning to appear and the bushes 

 were in full flower in northern Kansas. Other plants were 

 distinct!}' atlvanced, the panicles of bluegrass (Poa /^nUcnsis) 

 ripened, and the first pods of the early cruifers {Thlaspi, 

 Lcpidiuni, Sophia) falling. 



At Beatrice, Nebraska, the first sunflower head was 

 seen but it was yet early for them. A low evening primrose 

 with inconspicuous flowers {Oenothera laciniata) and the 

 clumps of Silphiuni integrifoliuni not yet in flower were noted 

 for the first time. At Marysville, Kansas, the first flowers 

 of Mullein {Verbascunt thapsns) appeared, and the spear- 

 like fruits of porcupine grass {Stipa spartea) were mature 

 or nearly so. 



The journey afforded an interesting confirmation of the 

 diflference in flowering period of the two sw^eet clovers. The 

 flowers of Melilotns officinalis were observed at Granite 

 Falls, Minnesota, and were abundant thereafter. A single 

 plant of M. alba in blossom was seen along tiie track at 

 Garretson, Minnesota, but scarcely any others until Lincoln 



