CATALOGUE. 195 



sionally two flowering branches are found on the same plant, or three 

 pairs of leaves in place of two, or, very rarely, the upper involucral leaves 

 bear one or even two axillary flowers. 



Gentiana Wislizenii, Engelin. I. c. pi. 7; Gray, Syn. 119. — Annual, 

 erect, a foot or less high, with the habit and the many-flowered thyrsoid- 

 paniculate inflorescence of the next ; leaves from lanceolate to ovate, 1' or 

 less long, with an obtuse or subcordate base ; calyx of barely half the 

 length of the tube of the corolla, with very small teeth, its membranaceous 

 tube cleft, and often, in age, dejected; corolla pale purplish, 4-5" long, acute 

 lobes fringed above the base; capsule linear; seeds subglobose. 



White Mountains of Arizona, Rothrock (799), in 1874. This is the 

 only known locality within our flora of this rare plant, which was discovered 

 by Dr. Wislizenus over thirty years ago in the mountains west of Chi- 

 huahua. 



Gentiana Amakella, L., var. acuta, Hook. f. Gray, Syn. 118. (G. 

 acuta, Michx.). — Annual, 2-20' high; stems wing-angled, usually much 

 branched; lowest leaves obovate, petiolate, upper ones lanceolate sessile; 

 inflorescence paniculate or strictly thyrsoid, with shorter erect or in some 

 forms with elongated patulous peduncles; calyx deeply 5-cleft; herbaceous 

 lobes lance- linear, somewhat unequal, often as long as the tube of the 

 bluish-purple corolla, the lobes of which are oblong, obtusish, beset at base 

 with copious (or in the diminutive alpine form, few) setae ; sessile capsule 

 linear; seeds subglobose. 



Grassy places in the mountains of Colorado and northeastward. The 

 true European Q. Amarella has usually 4-parted flowers 



Halenia Rothrockii, Gray, Proc. Amer. Acad. 11, 84; Syn. 127. — 

 Annual, a span or two high, loosely flowered ; lower leaves small, spatulate, 

 those of the stem distant, lance-linear, the uppermost closely approaching 

 subverticillate ; flowers cymose-subumbellate, on slender peduncles, often 

 in sevens, nearly 6" long, bright yellow, ovate, acute lobes a little longer 

 than the campanulate tube, the five spurs curved, horizontal or ascending, 

 half as long as the corolla; stamens from the throat of the tube; anthers 

 versatile ; seeds subglobose-ovate 



On Mount Graham, at 9,000 feet altitude ; in flower in September, 



