94 BOTANICAL GAZETTE [august 



Species of the vernal floral aspect 



Facies. — Poa pratensisf (base of slopes and in depressions). 



Principal species. — Spiesia Lamberti sericea, Sisyrinchium angustifolium,f 

 Antennaria campestris,*t Spiesia Lamberti, Castilleja sessiliflora.f 



Secondary species. — Viola pedatifida,t Oxalis violacea,t Lithospermum 

 canescens, Carex Meadii,t Meriolix serrulata, Hedeoma hispida, Plantago 

 Purshii,t Antennaria neodioica,t Lithospermum angustifolium, O.xalis stricta, 

 Carex festucacea,t Polygala alba, Poa compressa,t Astragalus crassicarpus.*t 



Tertiary species. — Pentstemon gracilis, Nothocalais cuspidata, Linum 

 rigidum, Lappula texana. Astragalus plattensis, Gaura coccinea, Senecio platten- 

 sis, Psoralea esculenta, Vicia linearis, Osmodium molle. Astragalus hypoglottis, 

 Viola cucullata. 



Ruderal species. — Lepidium virginicum, Melilotus olTlicinalis,t Melilotus 

 alba,t Lappula Lappula. 



* From earlier aspect. t Forming associations. 



The first week in May is marked by the flowering of Nothocalais 

 cuspidata and Lithospermum angustifolium. The sohtary yellow 

 head of the false calais, frequently 5'"^ in width terminating a long 

 (20 to 30'^'") naked scape, makes it very conspicuous, though it is 

 never more than sparse to subcopious. It is largely confined to 

 loosely sodded ridges and high slopes, and is pronouncedly of xero- 

 phytic tendencies. It is perennial by an excessively thickened root. 

 The achenes are heavily provided with pappus, assuring a wide 

 dissemination. 



Nothocalais has scarcely bloomed before the puccoons are in 

 flower, L. angustifolium appearing several days before the hoary 

 puccoon (L. canescens). The former with its terminal leafy racemes 

 of light-yellow flowers and its sparse occurrence remains an incon- 

 spicuous element. The hoary puccoon occurs throughout with the 

 other, but more abundantly. Its orange-yellow flowers in a compact 

 leafless umbel make it perhaps the most conspicuous though it is not 

 the most abundant element in the vernal aspect. Both of the puccoons 

 are abundantly pubescent and in their structure and distribution 

 show marked xerophytic tendencies. They are perennials by deep 

 thick roots. The smooth nutlets preclude all but a very limited 

 migration. 



Castilleja sessiliflora, Viola pedatijida, Oxalis violacea, Sisy- 

 rinchium angustifolium, and Spiesia Lamberti sericea bloom pro- 



