1919] RAMALEV— SACRAMENTO PLAINS 385 



with dried plants of meadow-foam, showing that the early spring 

 aspect also had been of the usual type. Subordinate elements of 

 the marginal ring were chiefly introduced weeds, Silene, Lepidium, 

 Hypochaeris, Rumex. 



The changing appearance of the depressions following the 

 advance of the season may be shown best by a tabular statement. 



PREVERNAL ASPECT 



Central area. — Scattered plants of Eryngium left over from 

 the previous season, but most of the ground bare. 



Marginal zone. — Floerkea forming a more or less dense ring 

 extending out to the ordinary grassland. The ring is often invaded 

 toward the outside by species of the adjacent area, such as various 

 native clovers, Orthocarpus, and European weeds. 



MID-VERNAL ASPECT 



Central area. — Eryngium actively growing but not yet of full 

 size. Allocarya develops and blooms at the true beginning of 

 spring; often forms a close community. Baeria and Lasthenia, 

 if present at all, are likely to appear early. Mimulus sparingly 

 present. Young plants of Alopecurus becoming abundant. 



Marginal zone. — Deschampsia nbw showing definitely as a 

 close growth of young plants. Native clovers in flower and fruit. 

 Young plants of Achyrachaena. Introduced weeds. 



LATE VERNAL ASPECT 



Central area. — Eryngium now taller and more conspicuous 

 than before. Allocarya continued from the previous aspect, but 

 the plants now in bloom are depauperate. Baeria and Lasthenia 

 in fruit or now drying up, with a few belated ones still blooming. 

 Alopecurus, Mimulus, Gilia leucocephala, Psilocarphus, and Down- 

 ingia in flower and fruit. In many places the last named very 

 abundant and giving character to the entire depression. 



Marginal zone. — Deschampsia in flower and fruit. Down- 

 ingia scattered through the inner part of the marginal zone. Native 

 clovers and Orthocarpus in fruit. Achyrachaena mollis in fruit. 



