MEXICAN AND CENTRAL AMERICAN UMBELLIFER^ I49 



1. Prionosciadium cuneatum C. & R., sp. nov. 



Plant 18 to 34 dm. high, with glaucous stem ; leaf-segments scabrous 

 above and pubescent on the veins beneath, oblong in outline, irregu- 

 larly pinnatifid-lobed or crenate-lobed, usually acute, each pair of seg- 

 ments joined to the one below by the broad wings of the rachis, which 

 form a series of conspicuous wedges connecting the segments ; inflor- 

 escence widely spreading, with verticillate primary branches and long 

 peduncles (7."^ to 10 cm. long); fruit oblong, about 10 mm. long, 

 wings not as broad as body. 



Jalisco : on grassy slope of barranca near Guadalajara, Pringle 3868, 

 September 12, 1891 (distributed as P. fringlei) \ between Bo- 

 lanos and Guadalajara, Rose 3047, September 21, 1897; on bar- 

 ranca near Guadalajara, Rose & Hoiigh 4822, July 9, 1899. 



2. Prionosciadium serratum C. & R., sp. nov. 



Plant 6 to 15 dm. high, with pubescent stem; leaf-segments some- 

 what scabrous above and slightly pubescent beneath, oblong to ovate 

 in outline, more or less lobed, sharply serrate and mostly obtuse ; the 

 wings of the rachis very conspicuous and serrate, somewhat narrowed 

 below; inflorescence often compact, of a few short verticillate pedun- 

 cles; rays 10 to 20 mm. long; pedicels 2 mm. long; fruit broadly ob- 

 long, 8 to 10 mm. long, wings broader than body. 



Durango : in the mountains of Southern Durango, Rose 2343, 

 August 16, 1897 ; on the table-land between Colotlan and Bolanos, 

 Rose 2836, September 8, 1S97. 

 Jalisco : on the slopes of the barranca near Guadalajara, Pringle 

 3886, September 18, 1891 (distributed as P. mexicanut)i). 



3. Prionosciadium acuminatum Robinson in litt., sp. nov. 



Stems 12 to 18 dm. high, glabrous or nearly so; leaves large, twice 

 ternate ; leaflets ovate, acuminate, more or less lobed and cleft, irregu- 

 larly and sharply serrate; peduncles short and slender; rays 12 to 18 

 mm. long; fruit oval or oblong, 8 to 10 mm. long, retuse with cordate 

 base ; dorsal and intermediate ribs indistinct ; wings thin, as broad as 

 body ; seed with involute face, rather broad sulcus, and little, if at all, 

 indented beneath the small oil-tubes. 



Jalisco : in barranca near Guadalajara, Pringle 3S64, September 



12, 1891, also Prifzgle 7634, June 10, 1898; same barranca, 



Altamirano 19, October 1S91, and Rose 3057, September 22, 



1897; same station. Rose & Hough 4820, July 9, 1899. 



Pringle 3864 was distributed as a variety of P. ?nexicanum^ but 



it seems to deserve specific rank. 



4. Prionosciadium nelsoni C. & R., sp. nov. 



Coarse herb, 12 to 18 dm. high, somewhat glaucous, more or less 

 branched; basal leaves large, on long petioles (3 dm. or more long), 

 twice pinnate; the primary and secondary rachis with toothed wings; 

 ultimate segments lanceolate, acuminate, sharply and doubly serrate, 

 somewhat puberulent on both sides ; upper leaves opposite ; upper 



