Thysanocarpus. CRUCIFERiE. - 113 



rather unsatisfactorily separated by its l-celled, 2-4-ovuled, 1-seeded fruit; the 

 silicels falling off without dehiscence but possessing valves, which divide regularly 

 under the prolonged infiuence of moisture. From the European genus Clypeola 

 of similar habit it is technically separated by the absence of any membranous or 

 tooth-like appendages upon the filaments. — Bull. Calif. Acad. Sci. i. 72 ; Prantl 

 in Engl. & Prantl, Nat. Pflanzenfam. iii. Ab. 2, 191. [By B. L. Robinson.] 



A. pusillus, Greene, 1. c. Hirsute-tomeutose, branched from near the base, 3 to 9 inches 

 high ; brandies subsimple, spreading, terminating in elongated racemes : leaves oblauce- 

 olate, obtuse, toothed or pinnatifid, 4 to 6 lines long, forming a rosette at the base ; the cauline 

 more or less reduced : pedicels I to 1^ lines in length, recurved : flowers very small : petals 

 minute, linear, or wanting : fruit f to 1 line in diameter, usually covered with spreading 

 uncinate hairs. — Tliijsanocarpus pusillus, Hook. Ic. t. 42; Torr. & Gray, Fl. i. 119. 

 T. oblongifolius, Nutt. in Torr. & Gray, 1. c. 118. — Dry hillsides from San Diego, Orcutt, 

 to Brit. Columbia, Macoun ; common. 



Var. glabrior, Watson, in herb. Leaves thin, nearly smooth, at least not hirsute ; fruit 

 ciliated but glabrous upon the faces. — Growing with the typical form near Fort Mohave, 

 J. G. Lemmon, April, 1884. A form with pods smootli and free even from ciliation has been 

 collected near San Francisco, 3Irs. Brandegee. 



3. THYSANOCARPUS, Hook, {©vaavos, fringe, and KapTro?, fruit.) — 

 Slender erect annuals of the Pacific Slope, with subsimple or branched stems, 

 minute white or purplish flowers, and very characteristic disk-shaped or concave 

 indehiscent one-celled fruit ; the latter often toothed like a cog-wheel or per- 

 forated near margin by a series of openings. — Fl. Bor.-Am. i. 69, t. 18, f. A; 

 Benth. & Hook. Gen. i. 94; Brew. & Wats. Bot. Calif, i. 48, excl. T. pusillus. 

 [By B. L. Robinson.] 



* Stem profusely branched ; branches spreading at a considerable angle, commonly again 

 once or twice branched : petals purplisli or white, considerably exceeding the calyx : pods 

 small (1^ to 2 lines in diameter), often strongly concave and boat-shaped with a condupli. 

 cate divided or perforated wing. 



T. conch uliferus, Greene. Glabrous throughout, glaucous, 4 to 8 inches in height: 

 leaves linear or lance-linear, sagittate-auriculate, runcinately tootlied or parted ; teeth 2 to 4 

 pairs : racemes 1 or 2 inches long, rather densely many-flowered : ])edicels 2 to 3 lines long, 

 spreading horizontally and gently recurved : pod markedly cymbiform, finely reticulated 

 but quite glabrous. — Bull. Torr. Club, xiii. 218, & Pittonia, i. 31; K. Brandegee, Zoe, 

 i. 132. — Rocky soil on the Island of Santa Cruz off coast of S. California, Greene, 

 Brandegee. 



Var. planiusculus, Robinson, n. var. Fruit plano-convex or slightly concavo- 

 convex, not perceptil)ly reticulated but hirsute upon both sides : pedicels 4 to 6 lines long. 

 — Island of Santa Cruz with type, T. S. Brandegee, April, 1888. 



* * Stems simple or with a few subsimple elongated nearly erect branches : pods 2 to 4 

 lines in diameter, plano-convex, rarely a little concave on one side ; wing entire, divided, 

 or perforated : flowers very small : petals little exceeding the calyx : upper leaves 

 narrow. 



T. CUrvipes, Hook. Commonly more or less hirsute below, 8 to 12 inches in height : basal 

 leaves rosulate, often persisting, oblong, pinnatifid with short blunt lobes or merely dentate ; 

 upper leaves lanceolate or linear-lanceolate, sagittate-auriculate and clasping at base, short 

 (6 to 10 lines in length) : pedicels very slender, 1| to 3 lines long, leaving the axis at right 

 angles and strongly recurved : fruit subject to much variation, 1 to 2i lines in diameter 

 (including wing), tomentose or glabrous; wing narrow or broad, usually entire, sometimes 

 crenate or with a few perforations, sometimes involute (var. involutus, Greene, Fl. 

 Francis. 275).— Fl. Bor.-Am. i. 69, t. 18, f. A; Torr. & Gray, Fl. i. 118; Brew. & Wats. 



