g2 BOTANICAL GAZETTE [AUGUST 
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pubescent with stellate hairs. It is scarce and its small white flower 
inconspicuous, so in no respect does it influence the floral tone. 
Ranunculus is even more restricted, occurring sparsely on lowest 
slopes and in depressions on the higher slopes, and is apparently 
related to a high water content of the soil. Its yellow petals soon 
fall, and its presence might easily be overlooked in a casual survey 
of the formation. It is a perennial and is an index of mesophytic 
conditions. Astragalus, with its racemes of violet-purple flowers, 
is easily marked in the formation. While generally distributed, its 
abundance is sparse to subcopious, yet frequently it assumes a gre- 
garious habit. It is a perennial of thickened tap roots which branch 
above and eventually fragment behind, establishing new individuals. 
Its migration is slow; dispersal is effected mainly by gophers, which 
store the fruits for winter consumption. However, ecesis is very 
certain. 
Vernal floral aspect 
Toward the last of the first or the beginning of the second week in 
May there is a floral outburst inaugurated by the blooming of Notho- — 
calais cuspidata and Lithospermum angustifolium, closely followed 
by Castilleja sessiliflora, Lithospermum canescens, Viola pedatifids, 
and Oxalis violacea, which marks the inception of the vernal floral 
aspect. Forms are now progressively added up to about the first 
week of June, when the aspect is distinctly terminated by the general 
blooming of certain sod-formers. Astragalus crassicar pus and Rani 
culus ovalis have extended over into this aspect, the former reaching 
its maximum flowering about the second week in May, thus entering 
conspicuously into the vernal period. The fruiting scapes of Pet 
cedanum nudicaule enter into the tone, while Antennaria campesiris a 
with its white fruiting heads is now more noticeable than earlier. A 
The deadened brown tone of the prevernal aspect is at last relievee < 
and replaced by the green of the grassy sod, which is rendered some 
what bizarre by the very general distribution of some twenty-eight : 
flowering forms, the largest number occurring in any aspect. 
floral facies is developed except in the case of Poa pratensis at bar : 
base of slopes, and then only in the later part of the aspect. 
of the prairie annuals have by the later part of the aspect - 
