34 



leaflets, and more regularly compounded umbels, seems to be 

 naturalized near Buffalo, X. Y. (G. W. C/into?i), Cincinnati, Ohio 

 (C. G.Lloyd, Bot. Gazette, iv. 148), and Painesville, Ohio ( W. 

 C. Werner). 



C. I.ATIFOI.IA L., with pinnate leaves having few subpinnatifid 

 leaflets, and large spiny fruit, has been found on ballast ground 

 near Philadelphia ( /. C. Mart'indale). 



8. TREPOCARPUS Nutt. inDC. Mem. Umbel. 56.— 

 Glabrous annuals, with thin pinnately decompound leaves and 

 linear segments, lateral few-rayed umbels opposite the leaves, in- 

 volucre and involucels of few linear entire or divided bracts, and 

 white flowers. 



1. T. iEthusae Nutt. 1. c. From a few inches to 3 feet 

 high: umbels 2 to 5-rayed; umbellets few-flowered, with very 

 short pedicels: fruit 4 or 5 lines long. (Fig. 4.) 



Prairies, from Arkansas to Louisiana, Texas, and Indian Territory. 

 FI. June and July. 



4. BIFORA Hoffm. Umb. Gen. 191.— Slender smooth an- 

 nals, with leaves pinnately dissected into filiform segments, in- 

 volucre and involucels of few small bracts, and white flowers in 

 few-rayed umbels. 



1. B. Americana Benth. & Hook. Gen. PL i. 920. A foot 

 or more high, branching above, rays and angles of stems (espec- 

 ially summit of internodes) roughened with minute callous points: 

 umbels 5 to 8-rayed; rays 6 to 9 lines long; pedicels about a line 

 long: fruit li^ lines long, 2i/< lines broad. (Fig. 5.) — Atrciua 

 Americana DC. 



Dry ground, mostly in Texas, and extending into Arkansas. Tlie 

 reference of this species to Missouri (Trari/), in Bot. Gazette, xii. 295, was 

 a mistake. 



B. RADIANS Bieb, from the Mediterranean region, has been 

 collected on ballast near Philadelphia, Penn. {Martindale) and 

 Providence, R. I, (^Bennett) 



5. CORIANDRUM Linn. Gen. n. 356.— Annual slender 

 branching glabrous herbs, with pinnately compound leaves, no 



