MEXICAN AND CENTRAL AMERICAN UMBELLIFER^ I51 



Chihuahua : ledges of river canon near Guerrero, Pringle 1251, in 



18S7. 



9. Prionosciadium macrophyllum C. & R., sp. nov. 



Glaucous, nearly glabrous throughout, 18-36 dm. high; leaflets (in 

 contrast with P. madrense) regularly segmented, the segments ovate, 

 more sharply toothed or lobed ; umbel with 8 to 10 nearly equal fruiting 

 rays, no involucre or of several linear bracts, and involucel of several 

 narrow bractlets ; rays 20-25 mm, long; pedicels 5-6 mm. long; fruit 

 almost orbicular, 10 mm. long, with wings broader than body, and 

 prominent dorsal and intermediate ribs. 



Jalisco : rocky banks of river. Fall of Juananacatlan, Pringle 3889, 



October 6, 1891. 

 Durango : near El Salto, Nelson 4554, in 1898. 



Zacatecas : rocky side of barranca near Monte Escabado, Rose 

 3589, August 27, 1897. Differs somewhat from the Pringle 

 specimen, which is the type, in having larger leaf-segments and 

 somewhat scabrous inflorescence. 



10. Prionosciadium dissectum C. & R., sp. nov. 



Glabrous throughout; leaves ternate then pinnately dissected ; the 

 idtimate divisions narrow, long-acuminate, and laciniately toothed; 

 umbel with i 2 to 25 nearly equal fruiting rays, no involucre, and in- 

 volucels of several linear bractlets; rays 10-35 nnm. long; pedicels 

 2-3 mm. long; fruit oblong, 10 mm. long, the wings about as broad 

 as body or a little narrower. 



Jalisco : between San Cristobal and Guadalajara, Pringle 3002, 

 August II, 1889; Rose -T^ooo, September 22, 1897; on barranca 

 near Guadalajara, Rose S Hough 4S09, July 9, 1899. 



11. Prionosciadium durangense C. & R., sp. nov. 



Glabrous throughout ; leaves ternate then much dissected ; the ulti- 

 mate divisions shorter than in P. dissechun and not acuminate, irreg- 

 vilarly toothed or entire ; umbel with 6 to 8 nearly equal fruiting rays, 

 no involucre, and involucels of several linear bractlets ; rays 15-25 mm. 

 long; pedicels 2-3 mm. long; fruit oblong, 8-10 mm. long, the wings 

 as broad as body. 



Durango: Sierra Madre, 15 miles north of Guanacevi, altitude 

 2250-2550 meters. Nelson 4763, August 17, 1898. 



Nearest to P. dissectum^ but with very different foliage. 



12. Prionosciadium watsoni C. & R. Proc. Am. Acad. 25: 150. 1890. 

 Peucedanuin mexicaniiin Watson, Proc. Am. Acad. 17 : 361. 1882. 

 Leaflets linear to lance-linear, 5 to 7.5 cm. long, prominently toothed 



or lobed; upper leaves with prominent scarious sheaths; fruit nearly 

 orbicular, with broad wings. 



Guanajuato : near town of Guanajuato, Rose it Hough 4840, July 



II, 1S99. 

 San Luis Potosi : Parry & Palmer 288, in 1878; Las Canoas, 

 Pringle 3822, in 1891. 



