76 



(hiiiKs^ \A\. j'iVi/ic///arc/ts Gra\-, Ain. jour. Sci. 2. xxxiii. 408. 

 C. a///sa///s Gray, Proc. Acad. Philad. 1803, ()8. 



Mountains, from Colorado and Utah to N. W. Wyoming and Oregon. 

 Fl. June to August Tiiis is Ifall ,(• Ifdrhanr 22. 



18. CYMOPTERUS Raf. Jouni. Phys. 1819, 100.— Mostly 

 \i)\\ and glabrous perennials (often ccspitose) from a thick elong- 

 ated root, with more or less pinnately compound leaves, mostly no 

 involucre and prominent involucels, and white, purple, or yellow 

 flowers. 



This genus has heretofore seemed polymorphous and perplexing on 

 aceount of having been made to contain species which hekl no relation to 

 it. As restricted here, it is quite definite and distinct, being easily recog- 

 nized by the broad thin wings of the fruit, which is not atalldoisally 

 llattened, the concave seed-face (often enclosing a central cavity), and the 

 entire absence of strengthening cells. At the same lime, the fruit charac- 

 ters are so diverse as to make the species easy of distinction. The genus 

 is confin-)d to Western North America, and especially the Great Basin, 



* Seed-face slio/it/v co)icave. 



f Floxvers zvhite. 



^ Itivoliicrc //one. 



Oil-t/(bcs /i/tnie/-o//s. 



1. C, glomeratUS Raf. 1, c. Low ( ;j to 8 inches), with a 

 short cau.dex bearing leaves and peduncles, glabrous: leaves pin- 

 nate to bipinnatc; ultimate segments linear-oblong, entire or 

 toothed: rays and pedicels very short, making a rather compact 

 cluster; involucel of a single palmately 5 to 7-parted bractlct: fruit 

 globose, 8 to 4 lines in diameter, v/ith 8 to 5 broad thin wings on 

 each carpel: oil-tubes small, 4 or 5 in the intervals (or double the 

 number where a rib has been suppressed), 8 on the commissural 

 side: seed-face almost jilane. ( Fig. 77, ) 



From Colorado to British Columbia, east to Saskatchewan. Wisconsin 

 iLai)li(nii). Iowa (Bi'saeij}, and Arkansas iXutlall). 



2. C. campestris Torr. <S: Gray, Fl. i. 024. Low (2 to 8 

 inches high), with short caudex from a tuberous root: leaves bipin- 

 natc, with oblong segments: peduncle scarcely as long as leaves; 

 umbels 8 to 4-rayed, with involucels of minute bractlets: fruit with 

 somewhat thickened wings, the dorsal or both intermediate ones 



