CALIFORNIA ACADEMY OF SCIENCES. 127 



The species will corne in between E. compositum f and E. 

 Lobbii, having umbels more divided than even the former, 

 by which it is more readily distinguished from E. Lobbii 

 than by any difference in foliage or perianth. The caudex 

 of the latter is seldom at all branched, but in E. rdbustum it 

 is excessively so, each plant forming a mat of a foot or 

 more in width. The peduncles are in the former not "de- 

 cumbent" but lie flat on the ground their whole length, the 

 dense, simple umbel itself resting on the soil; in the latter 

 thev are not even decumbent, but firmly erect from the base. 



