120 



42. VEL.EA DC. Prodr. iv. 230.— Glabrous or pubescent 

 perumiials, from thick elongated roots, with mostly radical pinnate 

 or ternate leaves, involucre present or wanting, conspicuous invol- 

 ucels, and yellow flowers. — Dcivcya Torr. and Gray, Fl. i. 641. 

 Arracacia iJenth. i\: Hook. (ien. Plant, i. S.S4, in part. 



There is no doubt lliat our spt'cies that liave been dew-ribed und<'r 

 hcirvtjii are the .•saiuc geiieiically as the Mexiean Vchru, ar.d as such must 

 bear tlio older name. Beiitham A: Hooker have referred the j,'roup to Ai- 

 raraiio. from which it seems to us sullieiently distinct to be retained as an 

 independent genus. Watson (Proc. Am. Acad. xxii. 4i:») unwillingly came to 

 tiie same conclusion and transferred the more recent species of Deireifu to 

 Arntcdciu. A study of the internal fruit-structures emphasis^es a distinc- 

 tion which seemed to be too sliglit upon external characters. The genus, 

 although somewhat polymorphous in habit, is consistent enough even in 

 that regard, with its thick elongated roots, mostly radical pinnate or ter- 

 nate leaves, and yellow flowers. The contrasting characters with A»ru- 

 rarid are as follows: Arnieinhi lias a som-^what beaked fruit, with broad 

 corky e<iually distant ribs (giving a i>entagonal carpel section), a prominent 

 well defined group of strengthening cells beneath each rib, single large oil- 

 tubes in the intervals, and a conical stylopodium. YeUca has beakless 

 fruit, with filiform unequally placed ribs (the dorsal being approximate), 

 very small ill-defined groups of strengthening cells, numerous oil-tubes 

 (in some cases almost continuous), and a depressed stylopodium. The 

 character of dorsally suleate or terete seeds has been used, but adds noth- 

 ing, as any large solitary oil-tube may have a sulcus developed beneath it. 

 Numerous intervallate oil-tube^ never are accompanied by a dorsally sul- 

 eate seed. The result is that Aintcurhi nnxy or may not have dorsally 

 hulcate seeds, whih; Velauiwyav has;butthis is only another way of saj'ing 

 that the former has large solitary oil- tubes in the intervals, and the latter 

 numerous oil-tubes. 



I. V. arguta. One to 2 feet high, glabrous, mostly with a 

 few cai'line leaves: leaves simply pinnate; leaflets o to 7, ovate, 1 to 

 1 ^^ inches long, the lowest pctiolulate and often subcordate, finely 

 and sharply mucronate-serrate, the terminal often 3-lobed : umbel 

 12 to 10-rayed, mostly with no involucre, and involucels of few 

 linear acuminate bractlets; rays 2 to 8 inches lontr; pedicels short: 

 calyx-teeth prominent: fruit oblong, smooth, 2'.^ to 3i/2 lines long, 

 acutely ribbed: oil-tubes 3 to 5 in the intervals, 4 to 6 on the com- 

 missural side. — Dcxccya argitta Torr. <Jv: Gra} , Fl. i. 041. Arra- 

 cacia arguta Benth. «& Hook. Gen. Plant, i 8S'». 



Mountains of S. California il'urrii a- Lemmini I-lSi. Bifieloic, Palmer 

 ll(»a, /'o;-/.s/( !)7!i): "N. Oalit." i Xulhill); also in Lower California ( 0/t»// 

 !M)7). 



