Gray as Herbarium ___ of Harvard University 0. 213 March 1984 Harvard University, Cambridge, Massachusetts contributions from the : é Rollins | Draba (Cruciferae) in Mexico and Guatemala Rollins | Sphaerocardamum (Cruciferae) MiaeOUFRi Baran icas SN 0195-6094 - he @ancen Liseaet Reed C. Rollins | Draba (Cruciferae) in Mexico and Guatemala Reed C. Rollins | Sphaerocardamum (Cruciferae) Published by THE GRAY HERBARIUM OF HARVARD UNIVERSITY ISSN: 0195-6094 Issued 9 March 1984 DRABA (CRUCIFERAE) IN MEXICO AND GUATEMALA REED C. ROLLINS In North America, Draba occurs primarily in temperate, mountainous, and arctic areas. There are no native species in Central America south of Guatemala, but in South America, beginning in the mountains of Colombia and Venezuela, the genus is well represented southward, especially in the Andes. Draba is the largest genus of the Cruciferae in the western hemi- sphere and in many ways it is taxonomically the most difficult. Part of this is attributable to the complexity associated with the large number of species involved, but to some degree it is due to the lack of adequate specimens of some of the taxa. This will be evident in the treatment that follows. In contrast to the situation north of Mexico, the Mexican representation of Draba is often an attenuation of the distribution of species with a wider geographic range. For example, D. standleyi Macbride & Payson and D. platycarpa T. & G. are presently known only ir in northeastern Laenuie from the Sierra Maderas del Carmen. Draba stanl. Texas to Arizona and D. platycarpa ranges from “Arkansas to Washington; D. cuneifolia Nutt., in the wide sense, is limited to northern Mexico but is widely distributed from Florida to Kentucky and westward to California. Some taxa follow the cordillera southward as does D. helleriana Greene, but again the southward extension is an attenuation of its total geographic range. There is, however, a group of interrelated species in south central Mexico and in Guatemala that is unrelated to those species found further north. Some tend to be associated largely with volcanic peaks: the disparate pop- ulations on these isolated peaks have posed —_ problems beginning with the earliest botanical exploration of the regio There are at least 12 species names available for “bi titabe of the high volcanic mountains of south central Mexico and Guatemala, yet our evaluation of the available specimens allows only two taxa at the specific level. Part of the difficulty arises from th that the two species, D. jorullensis Kunth ex H.B.K. and D. nivicola Rose; but part is the eval- uation and interpretation of the variation found. Bentham (1841) and Hem- sley (1879) had too little material for study to chart the variations of the isolated populations accurately. Apparently Rose (1903) minimized variation and emphasized diversity, for he described five new ‘species | from the area at one time. Unfortunately, he did not another; or for that matter, from the other four putative s species previcasly described from the same peaks. The fate of Rose’s proposed species has been about as might have been expected. One species and two taxa at the varietal level were recognized by Schulz (1927), and Hitchcock (1941) accepted one species and one variety from the lot. sd ets yee a carla i a specific name to survive, D. nivicola Rose. 2 Reed C. Rollins Some confusion appears to have been introduced by the name Draba jorullensis, the type of which, according to the field books of Humboldt and Bonpland, did not come from “volcano de Jorullo” as implied, but rather from Nevado de Toluca. Contrary to what was formerly supposed, the types of both D. jorullensis and D. tolucensis Kunth ex H.B.K. came from the same volcanic mountain, Nevado de Toluca. Although in growth form spec- imens of the type collection of D. tolucensis are more compact, and appear to be perennial instead of clearly biennial, as compared to those of D. jorullensis, both collections fall within the range of variation of a single species. With a much greater array of material than was available to Hitchcock (1941), we still came out with about the same evaluation of the taxonomic situation as he presented. Building on his treatment, the present contribu- tion extends the coverage to include newly discovered taxa and provides a presentation of all presently known taxa of Draba in Mexico and Guatemala. " KEY TO THE SPECIES A. Plant 2 1, [RS EE, rd L : Taae mg or ovules more than 10 in each hak hak leaves in a a flat rosulate cluster. = °s elliptical to obovate, rounded at apex, shes with simple — a sa 7 ei 1. D. B. "Siiques oblong, acute to phe: obtuse at apex, pubescent with simple or branched or glabrous, 8mm - wide — A. PL Ee beaman: where the sgmas may be nearly eae stanestn perineal qe iry sce not rosulate or if so not C. Fi con Tue twice the length of the sepals; styles slender, more than | mm. long: fruitin tsetideenghitrnh ohn artphende ascending to erect (except in D. cidade dans sii D. Basal ves petiolate, linear or oblanceolate, 3-8 cm. long, hirsute or at least margined large mostly si trichomes. with E. Basal leaves linear to narrowly oblanceolate, mostly less than 5 mm. segs pedicels thed in d. d leaf hases ne D. standleyi. E. lead ines Asse apiece aie pedicels widely spreading, from slightly tne ee ioe: D. rubricaulis. oblanceolate without a defined D.helleriana) eras racy nee, on a G. ns excerted; petals linear; fruiting pedicels 5 mm. or less long ee, Sines GC. Sta ig ae a Pe HES, ge os ee _— > 2.: rs E Oroadly sp aye els 7 mm. or Bae e saree neseee eee wee Draba in Mexico 3 H. Petals yellow; cauline | bl. late or none, >» When present more than | cm. long; stems aided or simple. I. Leaves — narrowed toward base; at least some stems on plants mostly bi I. Leaves “ae to oblong, not narrowed toward base; stems mostly ae aes ane; plants perennial. = Pe i. gait silvery-gray, realy taproot pa very cmt soni seeeeeciee 10. D. nivicola. J. Leaves glabrous to sparsely hirsute on the margins with coarse simple or forked trichomes, greenish, linear; taproot slender to uae ae sae" Seco eka cs . D. hidalgensis. 1. D. platycarpa Torrey & Gray, Fl. N. Amer. 1: 108. 1838. D. cuneifolia Nutt. var. platycarpa (T. & G.) S. Watson, Proc. Amer. Acad. 23: 256. 1888. GEOGRAPHIC RANGE IN U.S.A.: Arkansas and Texas west to nove a to bibs oe Mexico. Coahuila: Laguna Peak-E] Uno road, on steep N-facin olitic slopes, 29°0. N, 102°31'30” W, Sierra Maderas del Carmen, April 4, 1974, Wendt rs Riskind 132H pisah LL). This is the only specimen of D. platyc tycarpa we have seen from M 2. D. cuneifolia Nuttall in Torrey & Gray, Fl. N. Amer. 1: 108. 1838. For synonyms (none based on Mexican material) and a map showing the geographic distribution of var. integrifolia and var. sonorae, see Hartman et al. (1975). KEY TO THE VARIETIES Siliques with simple trichomes; lower _— hirsute with at least some coarse simple or — forked trichomes; styles scarcely evid Sili eee er ee re 4 to to > styles Sigues (3 nese mm. long, occurring on the distal one-half to = of infructescence . var. integrifolia. Siliques 3-6 (-8) mm. long, occurring on nearly entire length of PMT: ms. 2c. var. sonorae. 2a. D. cuneifolia Nuttall var. cuneifolia SS Oonitatte: RACE Dt C.44-: Ohio to northern Florida, 0 California. Sierra Juarez, 1.6 mi. Moran 14926 (GH); 21 mi. S of Santo Tomés, Wiggins 4274 (cH) ihuahua, 6 April 1886, it 8.n. (GH); Purpus 1026 (cH). Coahuila: Sierra ferred be Comet, be above Tinaja Blanca, Stewart 2261 (cn); Tinaja 2240 (GH); ca. 2 km. N J af "al, 1OA97C (TEX); 15 mi. S of ins + Tryon 58150 (GH, TEX); Sierra de . 1026a ( fi Agua, 0.7 mi. S from ranchi uth of canyon, Lat. tb 5" N, Long. 102°24'05" W, Tom Wendt et al. 1945 (eNcB). Zacatecas: 5 km. W of peion del Oro, M. C. Johnston et al. 10480D (rex); Puerto de Rocamontes, M. C. pc oranapet 10487A (TEx). 2b. D. cuneifolia Nuttall var. integrifolia S. Watson. Proc. Amer. Acad. 23: 256. 1888 GEOGRAPHIC RANGE IN U.S.A.: Texas to southwestern Utah, southern Nevada and central California. rosea a se los Angeles, ca. 4 mi. S of Las Flores, Wiggins me intains ca. 15 mi. S$ of Ensenada, Gentry 7926 (ENCB, 4 Reed C. Rollins MEXU); Sierra Judrez, 5 ee W of La Rumorosa, Moran 24110 (GH). Nuevo Leon: 24 mi. E of Saltillo, Rollins & Tryon 58104 (ENCB, GH, TEX); San | res ag 28 13719 (GH, MSC); 9.6 km. W of ._- de Agua de re genres Villaldama, C 3775 et al. (GH, TEX); just N of on de Potrerillos, M. C. Jo oe et al. 1024A eas 2c. D. cuneifolia Nuttall var. sonorae (Greene) Parish, Bull. S. Calif. Acad. Sci. 2: 81. 1903, based on D. sonorae Greene, Bull. Calif. Acad. Sci. 2: 59. 1886. GEOGRAPHIC RANGE IN U.S.A.: southern Arizona to southern Californ: Mexico. Baja California: Cafiada la Matanza, 4 km. S of Colonet, si 26830 (GH); Las Trincheras, Moran 12610 (GH); San Quentin, Palmer 611 (GH); Santa Maria plains, = 5 mi. § of Hamilton Ranch, Wiggins 4321 (GH); Santa Agueda, Palmer 207 (GH); margin of Laguna Chapala, J. R. & C. G. Reeder 6804 (ENCB); first cove east of Puerto Refugio, Isla — de la Guarda, Moran 8630 mies El Terminal, Moran 7930 (GH); Santo Domingo, (Hamilton’s Ranch and vicinity) Wiggins 4498 (cH, TEX-LL). maps northwestern mountains, 94 March 1884, Pringle s.n. (GH, isotype); 1 mi. S of Pinacate Peak, Sierra Pinacate, Felger eal. 19346 — Hourglass Canyon, ca. 2 mi. NE of Seca pases ) Tank, W side of Pi region, Felger 19158 (ENCB); 4 mi. W of Caborca, Keck 4037 (GH); San Bernardo, Rio hangs Coury 1361 (GH). 3. D. standleyi Macbride & Payson, Ann. Mo. Bot. Gard. 5: 150. 1918, based on D. gilgiana Wooton & Standley, Contr. U.S. Nat. Herb. 16: 124. 1913, not D. gilgiana Muschler, Fedde Rep. Nov. Sp. 3: 212. 1906. GEOGRAPHIC DISTRIBUTION IN U.S.A.: Texas to Arizona. Mexico. Coahuila: Si Sierra Maderas del Carmen, ¥s mi. N of Campo Dos along trail to Campo Tres, 28°59'30" N, 102°36'30" W, 7 Aug. 1974, Wendt ¢ Adamcewicz 524 (GH, MEXU, TEX). 4. D. corrugata S. Watson var. demareei (Wiggins) C. L. Hitchcock, Univ. Wash. Publ. Bot. 11: 33. 1941, based on D. demareei Wiggins, Contr. Dudley Herb. 1: 168. 1933. Variety corrugata, D. corrugata var. saxosa ripe Munz & Johnston and D. corrugata f. vestita (Davidson) C. L. Hitchcock apparently occur only in southern California, U.S.A. Variety demareei appears to be restricted to the —— San Pedro Martir of northern — California. ja California, Sierra San Pedro cpiths conde srerontecinstadieg si ee Corona, 35°59’ N, 115°35’ W, Moran ions = east slope of Cerro, 31°02’ N 115°27’ W, Moran 15267 (cH); Yerba Buena, 31°00’ N. 115°27' 5°27’ W, Moran ¢> Thorne 141422 (GH, TEX-LL); La Encantada, Wiggins & Demaree 4875 ses : 5. D. implexa Rollins, sp. nov. Herba perennis; caudicibus ramosis; caulibus simplicibus, 3-5 cm. longis; foliis basalibus, pubescentibus, oblanceolatis, 1.5-3 cm. longis, 2-3 mm. latis, ‘cckcecis val tems dows 4 foliis caulinis spathulatis, vel gis, cuneatis, integris, entibus; pedicellis divaricatus, 3-5 mm. longis; sepalis erectis, ibus, 3.5-4mm. longis, 1.5-2 mm. mal gsi panama ne ee eee 1.5 mm. latis; siliquis immaturis . =e, edged is 2.5-3.5 mm. longis; seminibus ignotis ‘Herbarium. or allan dlr goer Hue- huento), South of Huachicheles about 75 mi, W of fC. Durango, rocks, deep, \ p yation 2900-3. ames Maysilles 7290. Isotype: MIcH. mse Puy 1950.1 if , 2 Oe EN oe peers Rae © L c, mant , thickened with rem: imi of ie at cL ; stems leafy, cecal dnishy wabievess Draba in Mexico 5 with a mixture of small dendritically branched trichomes and fewer large simple or forked ones, 3-5 cm. tall; basal leaves oblanceolate, petiolate, entire or with one or two remote small teeth, obtuse, pubescent with coarse dendritic trichomes on blade surfaces, often margined with larger simple or forked trichomes particularly on the petioles, 1.5-3 cm. long, 2-3 mm. wide: cauline leaves overlapping, extending to inflorescence, spatulate to oblong, obtuse, entire, cuneate at base, 1-1.5 cm. long; inflorescence condensed, flowers congested; pedicels divaricately ascending, pubescent, 3-5 mm. long; sepals erect, hirsute with simple or rarely forked trichomes, 3.5-4 mm. long, 1.5-2 mm. wide, inner pair plain, outer pair slightly saccate and somewhat boat-shaped; petals spatulate with a narrow claw, truncate to slightly retuse above, yellowish, drying nearly white, 5-6 mm. long, ca. 1.5 mm. wide; stamens strongly tetradynymous, filaments slender, paired filaments ca. 3.5 mm. long, anthers oval to broadly oblong, ca. 1 mm. long; glandular tissue well-developed, surrounding base of single filaments, subtending base of paired filaments; immature siliques oblong, acute to acuminate at apex; glabrous on valve surfaces, usually pubescent with simple trichomes on the margins; styles slender, 2.5-3.5 mm. long; siliques of previous season twist- ed, ovate-lanceolate, 7-10 mm. long, 3-4 mm. wide; seeds wingless, oblong, ca. 1.5 mm. long, ca. 1 mm. wide, 6-8 in each loculus; cotyledon position not determinable. Draba implexa is not closely related to any other known North American species of the genus. The matting habit of growth is somewhat like that of D. smithii Gilg, a species of southern Colorado, but any close similarity stops there except that both have twisted fruits, a feature of many species of Draba. In having a cushion of dead leaf bases covering the caudices, D. implexa is similar to D. standleyi Macbride & Payson and D. petrophila Greene, but in most other characteristics these species have very little in common. The flower color of Draba implexa was indicated to be yellow by the collector. However, the dried specimens show the petals to be nearly white and I have assumed that the yellow pigmentation was lost during drying. An interesting feature of the holotype specimen is that there are successive tufts of dead leaf bases along the caudex branches. This probably indicates that, in successive years, the leaf bases have persisted but that after each depo- sition, some growth of the caudex branch has taken place before the following year's remnants were left behind. Unfortunately, D. implexa is known only from the one collection cited and very little of the variation presumably present in this species can be assessed. 6. D. rubricaulis Heller, Bull. Torr. Bot. Club 26: 262. 1899 D. helleriana Greene var. patens (Heller) Schulz f. ouivicoulie (Heller) O. E. Schulz. Pflanzenreich IV, 105: 185. 1927. Perennial; stems several from a loosely PEG caudex, tic or branched above, h i ng 6 Reed C. Rollins trichomes, usually glabrous above, 2.5-4.5 dm. tall; basal leaves petiolate, mid-vein prominent, oblanceolate, obtuse at apex, remotely dentate, sparse- ly pubescent with simple or forked trichomes (2-)3-7 cm. long, (5-)7-12 mm. wide; cauline leaves 3-6, sessile, oblong, entire to dentate, non-auriculate, sparsely pubescent with simple or forked (sometimes few-branched) tri- chomes, 2-5 cm. long, (5-)8-15 mm. wide; sepals yellowish, outer saccate pair wider than inner non-saccate pair, glabrous except for two or three large simple or forked trichomes toward apex, 3.5-4 mm. long; petals yellow, narrowly lingulate, erect, not unguiculate, not differentiated into blade and claw, 7-9 mm. long, 1.5-2 mm. wide; glandular tissue well-developed flank- ing base of single stamen filament, otherwise obscure; anthers oval, ca. 1.5 mm. long; fruiting raceme elongated, up to 2 dm. long; pedicels spreading at right angle to rachis to slightly ascending, nearly straight, glabrous, 8-15 mm. long; siliques ascending, oblong, twisted, acute at apex, glabrous or with short simple trichomes on the valve surfaces, 8-11 mm. long, 2-3 mm. wide; styles 2-3 mm. long; seeds light brown, plump, wingless, slightly longer than wide, ca. 1.3 mm. long; cotyledons accumbent. Mexico. mit of Sierra Mohinora, Correll ¢- Gentry 23160 (GH, TEX-LL); Mt. Mohinora, E. W. Nelson 4880 ( (GH); cool ledges, Sierra Madre, Pringle 1529 (cu, holotype). Draba rubricaulis is apparently restricted to the Sierra Madre of Chihua- hua. Hitchcock (1941) followed Schulz in his treatment of this taxon. How- ever, the petiolate basal leaves of D. rubricaulis and consistent simple or rarely forked trichomes on the leaves, stems, and pedicels are distinctive as compared with D. helleriana. Variety patens of that species is closest to D. rubricaulis but there is a large difference in flower size: those of D. rubri- caulis are much larger than those of var. patens. 7. D. helleriana Greene, Pittonia 4: 17. 1899. As interpreted by Hitchcock (1941), Draba helleriana consists of four varieties and one form, and has a combined distribution that includes south- ern Colorado, New Mexico, Arizona, and the Sierra Madre of Chihuahua. I recognize forma rubricaulis as a species distinct from D. helleriana as indicated above, but it is clear there is a close relationship between these two species. That D. helleriana is a complex of infraspecific taxa is also Material from Nuevo Leon not seen by Hitchcock extends the p pe The two varieties described below are strong p ]. i+} | Se A; + le ok <3 * most varieties of D. helleri } st the: cea + ok: branched. Se ee This is particularly true in D. Lis ae ee E. Schulz, to whieh the two following varieties appear to be most closely related. These varieties represent the species as it is presently known in Mexico. Draba in Mexico 7 KEY TO THE VARIETIES Plants with closely branching caudices and a thick taproot; stems mostly 1.5 dm. or less tall tosiensis. Plants sprangely in caudex area; stems 2 dm. or more tall .................... 7b. var. viejoensis. wes 2. helleriana ces var. upaineicnaie Rains, var. nov. , 6-18 cm. altis; siliquis glabris ey sparse i Holotype in the oC ‘Hodhddein m. Mexico, Nuevo Leon: Cerro Potosi, top of mtn., ca. 3650 m. alt., in alpine meadow, sa 1 July 1959, John H. Beaman 2665. I Mexico. Nuevo Leon: Cerro i, Galeana, G. B. Hinton et al. 17037 (ence, TEX), 17038 (ENCB, MSC), 17050 (ENCB, MSC, —— near summit of Cerro Potosi, Galeana, Sharp 45753 (cu); Dorr 2279 (TEx); C. H. Sage Cel 2273 (GH); Beaman 4457 rm ascent of Sierra Potosi by N hogback, ca. 20 mi. NE of Galeana, C. H. & M M. T. Mueller 1252 (GH, MEXU, TEX); Sierra La Marta, G. B. Hinton se 17973 (TEX). Field notes accompanying some of the specimens indicate that var. poto- siensis grows abundantly on boulders and in open areas and that the flowers are bright yellow. 7b. D. helleriana Greene var. viejoensis Rollins, var. nov. Herba perennis; caulibus 2-6 dm. altis; foliis basalibus late oblanceolatis vel obovatis; pedi- — 1-2. cm. longis; siliquis fe ee tibus. in the Gray Herbarium. Mexico, Nuevo Leon: Sie rra Madre Oriental, Cerro del Moog 15 mi. W of Dulces Nombres, iamsicipabity of icy . open, ne: — barren, limestone outcrops, 18 August 1948, F. G. Meyer & D. J. Rogers 2984 : Mexico. Nuevo Leon: San Antonio Pefia Nevada, Dr. Arroyo, G. y eid 17331 (ENCB); area of Cerro Pena Nevada, ca. 12 km. NE of San Antonio Pefia Nevada, 30 km. E of Dr. Arroyo, N slopes of mt. known locally as Picacho Onofre, Wells ¢ Nesom 452 (GH), — 2700 (msc); Picacho San Onofre, Zaragosa, G. B. Hinton et al. 17384 (ENCB forested area near microwave tower, shaded moist ravine, McGregor et al. 340 (cH). 8. ee PEO Rollins, sp. nov. : tha biennis; caudicibus simplicibus; caulibus 1-6, erectis, simplicibus, pubescentibus, 5- sparse hirsutis petalis spathulatis, ca. 2. - longis, ca. 1.2 mm. latis; divaricatis, , dense pubescentibus, 2-5 mm. longis, siliquis oblon- gis vel anguste ovatis, glabris vel sparse pubescentibus, 46 mm. longis, 2-3 mm. latis, loculis 4-7 ovulatis: se: *Sdlotype in she aay Herbarium. Custeasiie. H near lake at east end of Llano de Tierra, ca. 2.5 mi. W Lae de Sn Mig ca. 3500 m. alt. in wet meadow near lake shore, 2 August 1960, John H. Beaman 3965 : DUKE, ENCB, MSC, TEX. Biennial or pat perennial with 1-6 unbranched stems arising from a Hi Hh fr : erect or slightly curved upward at base 5-16 cm. tall; basal leaves oblanceo- late, obtuse, O ticulations, usually phere hee a a ee ee we eked aed alee 8 Reed C. Rollins dendritic trichomes, uniformly pubescent below with dendritic mostly 4- branched trichomes, 1-1.5 cm. long, 4-6 mm. wide; cauline leaves 3-5, ovate to broadly oblong, entire or with a few remote denticulations, densely pubescent with dendritic 3-5 branched trichomes, 4-10 mm. long; sepals broadly oblong to nearly elliptical, nonsaccate, hyaline-margined, hirsute with a few forked or simple trichomes, ca. 2 mm. long, ca. 1.5 mm. wide; petals whitish when dry, spathulate, truncate to slightly retuse, ca. 2.5 mm. long, ca. 1.2 mm. wide; stamens subequal, anthers nearly oval, ca. 0.2 mm. in diameter; glandular tissue well-developed above petal base and subtend- ing single stamen filaments; pedicels widely spreading to slightly ascending, straight, densely pubescent, 3-5 mm. long; siliques oblong to narrowly ovate, strongly compressed parallel to plane of septum, glabrous to sparsely pubes- cent along margins, 4-6 mm. long, 2-3 mm. wide; styles barely visible; stigmas nearly sessile; ovules 4-7 in each loculus; funiculi slender, ca. 1 mm. long; seeds immature, plump, wingless; ca. 1.2 mm. long, ca. 1 mm. wide; cotyledons accumbent. Guatemala. Huehuetenango. Sierra de los Cuchumatanes: at Chemal, Km. 318 on Ruta Nacional 9N, Beaman 3077 (Gu, msc); between Tojiah and Chemal at Km. 317 on Ruta Nacional , Beaman 3824 (GH, MSC); between Paquix and Chemal, Beaman 3006 (Msc); about 10.5 mi. SW of San Juan Ixcoy, W. D. Stevens 1254 (msc). Because of its biennial to short-lived perennial habit and unbranched caudex, Draba beamanii must be compared with D. jorullensis, which is probably its nearest known relative. But the stems are few and unbranched TL. roy 1 1 present, they do not fringe the leaves as in D. jorullensis. Also, the petals 9. D. jorullensis Kunth ex H.B.K., Nov. Gen. et Sp. Pl. 5: 78. 1821. For synonymy see Hitchcock (1941). n = 12, Beaman, et al. (1962). i Voleén de dering Beaman 4034 (msc); Vole4n Acatenango, Beaman 3285, 4034 (GH, MSc) ’ de Agua, Hartweg 571 (cu, isotype of D oe eo (Msc); Harmon 3663 (ENCB). San Marcos: Volc4n Tacna, A ) (GH, MSC Maria, Skutch 850 ; Beaman 4106 (Msc); Matuda 2348 (mexu ess vee Chiapas: iapas: Mt. Tacand, a Matuda s.n. (GH), Matuda 2348 (mexw); near conte of ion Judrez, D. E. Breedlove (ENCB); Breedlove 29376 (mExu). Jalisco: Nevado de Colima, McVaugh 11650 (cx); Beaman 2346 (msc, TEX); Goldsmith 61 (cx); A saan & Eiten 271 (cx), 297 (GH, msc). Mexico: Sierra de las Cruces, 11 Sept. 1892, Pringle 5260 Draba in Mexico 9 (GH, MEXU, type no. but wrong date for isotype of 2 confusa Rose); Serrania de age (Cerro de » Ajusco), _— 7385 (GH), 10266 (GH, MEXU, Msc), 15623 (GH, Msc); Beaman 2783 (cH, ; cero Agua Blanca, Hinton 4921 (cH); para id Beaman 1984 (GH, MSC), 2847 (cH, — TEX), peso New MSC); Nevado de Toluca, Hernéndez X. X10164 (cHapa); Beaman 1679, 1695 (GH), 1891 (GH, MSC), 2448 (GH, MEXU, MSC), 1890 (MEXU, MSC, TEX); Pringle 4248 (cu, MEXU i i Wendt & . Mexico-Pue Cristie 7466 (CHAPA); Correll 14308 (c - Beaman i 2106 (cH, ge Rose cH ay 5980 (GH). : 8581 (ENCB, , MSC, , TEX-LL). Si Ww Orizaba), Beaman 2521 (Msc). Tlaxcala: Malinche, Beaman 2229, 2257 (msc). Veracruz: Cofre - Perote, Beaman 2162 (GH, Msc); Dorantes Lopez 329 (GH); Dorantes et al. 01563 (ENCB); Gourlay B4614 (cHAPA). oo Draba jorullensis is very abundant on the volcanic peaks where it occurs for there are 52 specimens of it in the Gray Herbarium alone and I have examined well over 100 different collections. The popular peaks, such as Iztaccihautl, Orizaba, Popocatepetl, and Toluca have been collected most heavily with more than 15 different collections represented in some instances. I mention this because with as many samples as this to work with, it is clear, as it was to Hitchcock (1941), that this species is exceedingly variable. Without doubt, this is the basic reason for the unusual number of redundant names proposed for it. The habit ranges from compact individuals of low growth to those with greatly elongated stems and a sprangly growth form. Other features are similarly variable. I endorse the conclusions reached by Hitchcock (1941) and refer the reader to his paper for a further discussion of the variation present. 10. D. nivicola Rose, Contr. U. S. Nat. Herb. 8: 29. 1903. D. orbiculata Rose, ibid. D. nivicola var. orbiculata (Rose) O. E. Schulz, Das Pflanzenreich IV, 105: 166. 1927. Mexico. M alta Cerro Tldloc, Rzedowski 31559 (ENCB); Beaman 2328 (msc); Ries & Hay 5 5766 (cH, MEXU, isotypes); Beaman 1767 (ENCB, GH, MSC, TEX); 2270, 3629 (cH, MSC, TEX); Purpus 2800a (GH). Veracruz: Cofre de Perote, Beaman 2142 (GH, MEXU, MSC); Ortega-Oetiz 206 (cu); Dorantes-Lopez 328 (GH, MEXu); M. G. Zola et al. 72 (ENCB, MEXU). The specimens from Nevado de Toluca show silique variation from orbi- cular, as in the type collection of Draba orbiculata, to ovate, as in the type collection of D. nivicola. Most of the specimens are of the ovate type. I agree with Hitchcock (1941) that D. orbiculata makes a weak variety at best, but now with more and better material available for study than was available to him, it is difficult to make a case for recognizing two taxa. For this reason, I have listed D. orbiculata as a straight synonym of D. nivicola. at: D. hidalgensis Calderén, Bol. Soc. Bot. Mexico 31: 109, fig. 1. 1970. Mexico. Hidalgo. Pachuca: 6 km. al N de Pachuca, Cerro de las Ventanas, Rzedowski 26804 10 Reed C. Rollins (holoty d b blo N n road from Real del Monte to El Chico, Moore ¢ Wood 4086 ie ican Cerro de rs Ventanas, El] Chico, Al Gentry et al. 32176 (cu); Rzedowski 16999 (ENCB). The flowers and siliques of Draba hidalgensis are, in general, similar enough to D. jorullensis and D. nivicola to be allied with these species. However, it is distinctive and certainly merits recognition as a species. Its linear, nearly glabrous greenish leaves, are longer and not at all rosulate as in the densely pubescent rosulate and grayish leaves of D. nivicola. Even when the unusually wide variability of D. jorullensis and the lesser but substantial range of variation of D. nivicola are taken into account, the characteristic features of D. hidalgensis place it well outside either of those taxa. ACKNOWLEDGMENTS It is a pleasure to acknowledge financial support from the Roads Grant, provided by Mrs. Aileen G. Roads. LITERATURE CITED Beaman, J. H., D. C. D. DE JoncH & W. P. STourmIRE. 1962. Chromosome studies in the alpine floras of Mexico and Guatemala. Amer. J. Bot. 49: 41-50. —— G. 1841 [fascicle M, pp. 81-88]. Plantae hartwegianae I-IV + 1-393. London, 1839- 1 HarTMAN, R. L., J. D. sono F. BOHNSTEDT. 1975. nggingeier se of Draba cuneifolia and D. ‘ltyarya rae) with emphasis on volatile oil and flavonoid constituents. HEMSLEY, Ww. B. iva Diagnoses plantarum novarum vel minus cognitarum mexicanarum et centrali-americanarum. Pars Altera I “a7. Hirt C. L. 1941. Ares bas of western North America. Univ. Wash. Publ. Biol. Ll: 1-132. J. N. 1903. Studies of Mexican and Central American plants, no. 3. Contr. U.S. Natl. Herb. 8: 1-55. — O. E. 1927. Cruciferae - Draba et Erophila. In Engler, Das Pflanzenreich IV, 105. 1- SPHAEROCARDAMUM (CRUCIFERAE) REED C. ROLLINS Since it was published more than a century ago (S. Schauer, 1847), to my knowledge no specimens, other than the type, have been referred to Sphaerocardamum nesliiforme Schauer. Schulz (1936) recognized and illus- trated the genus, but failed to associate any other species with it. Instead, he (1933) proposed the monotypic genus Cibotarium, apparently not real- izing that C. stellatum (S. Watson) Schulz was in reality a second species of Sphaerocardamum. Schulz had an excellent opportunity to make the asso- ciation between S. nesliiforme and what Watson (1890) called Capsella stel- lata because he had the type of the former available to him in Berlin, as well as material of C. stellatum. Possibly Schulz was misled because Schauer emphasized the resemblance of Sphaerocardamum to Neslia so strongly in his original publication. Certainly I was not able to make the appropriate association of these species merely from the descriptions of Schauer or of Schulz, or from the illustration given in Die Pflanzenfamilien. Even photo- graphs of the type of S. nesliiforme, kindly supplied to me by Guy Nesom of Memphis, did not provide enough information for me to make the asso- ciation. It was apparent that Capsella stellata and Sphaerocardamum nesli- iforme were two species of the same genus only after I was able to see the type of S. nesliiforme itself. As a consequence of my studies, it is clear that Cibotarium must be abandoned in favor of Sphaerocardamum. My former treatment of the species involved, which are all native of Mexico (Rollins, 1941), was somewhat tentative because of the paucity of available material. Since then, I have been able to observe populations of these plants in the field on several occasions and to obtain some material for cytological ~paisdh (Rollins and Ridenberg, oad One species, Sphaerocar- damum greenhouse. However, there is still too little material for a Seked taxonomic treatment of the genus as a whole. Unlike many genera of the Cruciferae, Lesquerella for example, plants of Sphaerocardamum seem to be few in number where they occur and are often inconspicuous. This may account in part for the unsatisfactory representation of the genus in most herbaria. Information previously published under the name Cibotarium (cf. above and Rollins, Sai soptenlle se ens ee damum, and it is not ee ace oncsaae ees cites or 12 Reed C. Rollins Sphaerocardamum Schauer, rao 720. 1847. Cibotarium, O. E. Schulz, Bot. Jahrb. 66: 91. 1933 Biennial or perennial herbs, often me at cm stems one to several, branched at least above, densely pubescent throughout with dendritically branched trichomes; basal leaves lacking; cauline leaves linear-oblong to spatulate or oblanceolate, cuneate at base, entire to dentate or remotely denticulate, 1-nerved, densely pubescent; inflorescences racemose, termi- nating each branch; flowers small to minute, numerous; sepals oblong, pubescent, non-saccate, erect, usually hyaline-margined; petals spatulate, white, sometimes absent; stamens excerted, filaments subequal, anthers globose, usually purplish; fruiting ae slender, straight, pubescent, widely sr to oblong, densely pubescent on exterior, -, often pubescent o1 on laterior. styles glabrous; ovules 2 to 8 in each loculus; seeds wingless, oblong, plump, musilagenous when wetted; cotyledons incumbent to obliquely incumbent. This genus, as presented here, consists of 8 species that occur only in central Mexico. The geographic area extends from the states of Hidalgo and Aguascalientes, north to Coahuila and eastward to Nuevo Leon. Several taxa apparently are very restricted i ‘in their occurrence. The most widespread is which has been found in Coahuila, Nuevo Leo: and Zacatecas. On the basis of counts in S. stellatum and S. macro- petalum, the basic chromosome number appears to be x = 8. : or more in B. ge diel ciel ce obovate: cp gooey definitely keeled on back. C. Petals absent or minute, shorter than sepals if present; oe long; 2. S. stellatum. siliques 2 mm. or less long Cc. oe long; siliques 3 mm. ane —e as — rae se ded th “iets le, oblong or obovate to nearly linear; valves of D. _ Peadh uae ouestiien ered, i eet crt Petals 4. S. macrum. pip toners rms longer than sepals, obovate to spatulate; blade expanded, often “4 Siliques obovate; valves keeled on back 5 Ss. ramosum. a: Valves of nas cede uk: ack signs sas atiine oe hey gee plane . ies narrowly linear . - 6. S. compressum. siliques rounded on siliques moderat commpretaed cipposite to plane of septum; replum oblong. G. Petals spatulate, gradually tapering from blade to claw, eee erses long; S. divaricatum. Sphaerocardamum 13 G. Petals hig abruptly narrowed from blade to claw, 2-3 mm. long; styles 1-2 8. S. macropetalum. mm. 10) i; nee nesliiforme Schauer, Linnaea 20: 721. 1847. Cibotarium microcarpum Rollins, Rhodora 59: 70. 1957. Perennial, sometimes woody at base; stems single to rarely branched from base, virgately branched above, densely pubescent throughout with coarse dendritically branched trichomes, 1.5-2.5(-3) dm. tall; basal leaves not pres- ent; cauline leaves linear-oblong, cunneate at base, obtuse at apex, entire or remotely denticulate to shallowly sinuate-dentate, 1-nerved, densely pubes- cent with coarse dendritic trichomes, ees cm. long, up to 8 mm. wide; inflorescences racemose, terminating each branch; flowers minute, numer- ous; sepals oblong, pubescent, non-saccate, erect, hyaline-margined, 1 mm. or less long; petals minute, narrowly spatulate, white, shorter than sepals; stamens excerted, filaments subequal, anth bose; fruiting fF der, straight, pubescent, widely spreading, only slightly ascending, 2.5-3(-4) mm. long; siliques globose or nearly so to oval, disposed at same angle as pedicel, valves nearly hemispherical, rounded on back, densely pubescent on exterior, sparsely pubescent to nearly glabrous on interior, septum entire, replum nearly orbicular to wncinied ee | than broad, 1.2-1.5 mm. long; styles glabrous, 0.75-1.0 mm. long; ovules 2-3 in each loculus, funiculi usually attached near apex of replum; seeds wingless, oblong, plump, musilagenous when wetted, 1 mm. or less long; cotyledons incumbent to obliquely incum- lity, Aschenl |, holotype). Hidalgo: dry rocky slopes of Barranca ren ass tpicacatair Caaertynenadey 7.6 mi. from Zimapén on road to Se bik Enna del Toxo and Balcones, District of Zimap4n, Oct. - its H. E. Moore, ae rohae H, holotype; BH, isotype of Cibotarium microcarpum). Same general locality, Oct. 1 1983, R. C. & K. W. Rollins 83349 with Mario Sousa P. (GH, sad ks bes anced Following Schulz (1936), the original compounding of the epithet nesliae- f; se a | a ey eens, 7 oe L ee +. This is in accordance with Article 73 (73.8) of the International Code of Botanical Nomenclature. The single plant constituting the holotype of Cibotarium microcarpum is woody below the leafy portion of the stem. This is the usual situation in older plants of several species of Sphaerocardamum. Plants do flower the first year of growth and these have not, at that point, developed a woody foot that is otherwise characteristic. In S. nesliiforme, the two specimens constituting the holotype do not have a woody base. However, it is possible that these are plants not yet old enough to have developed wood. Not only is the extent of woodiness variable from plant to plant within species of Sphaerocarda- mum, there are considerable differences between species. Sphaerocarda- mum macropetalum and S. stellatum are more woody nee either a Tt catum or S. a There are o' ther slight ligh the hol terial of S —— te type Ff 14 Reed C. Rollins example, the siliques on the holotype of C. microcarpum are slightly stipitate whereas they tend to be sessile in S. nesliiforme. Also, in the one or two fruits of C. microcarpum examined, there were three ovules in each locule and the replum was a little more elongated than in S. nesliiforme where the ovule number is usually only 2 per locule. But these distinctions may well fall within the total range of variation of S. nesliiforme when that is better known. Therefore, C. microcarpum has been placed in synonymy. Because the genus Sphaerocardamum is not known south of the state of Hidalgo in Mexico and the mining areas of that state were visited by Aschen- born, the presumption is that the type of S. nesliiforme was collected some- where in that state. Acting on that assumption, we spent four days in Octo- ber, 1983, searching for S. nesliiforme in what we thought might be appropriate sites. Following the leads provided by the data from the collec- tions of Moore (no. 5443) and Moore and Wood (no. 4253a), we found S. nesliiforme and S. divaricatum in the same areas where they had been collected in 1949 and 1948 respectively. 2. S. stellatum (S. Watson) Rollins, comb. nov., based on Capsella stellata S. Wats., Proc. Amer. Acad. 25: 142. 1890. Ciloteriam stellatum (S. Wats.) O. E. Schulz, Bot. Jahrb. 66: 91. 1933. 2 25059 (ENCB). Coahuila: holotype); ca. 2 km. N of Estacion Carneros, E flank of Sierra E] Chorreadero, M. C. Johnston et al. 10497A - Carneros Pass, 26 mi. S of Saltillo, Rollins & Tryon 58133 et 29 mi. ia of Saltillo, & Roby 7490 (cH); Saltillo, Palmer 752 (om. Neovo Leon: 177 km. N of Matehuala, Rollins ¢- Roby 76067 (Gu). San Luis Posoti: 50 mi NE of San as Fotos on rad to Matehuala, Rollins ¢ Tryon 58191 (Gu). Zacatecas: ca. 15 (air) mi. E of Concepcion del Sierra del Astillero, Henrickson 13302b (cu). Like many other herbaceous to suffrutescent species of the milder, arid parts of North America, Sphaerocardamum stellatum may produce inflo- rescences a few months after seed germination. This was shown when seeds planted in the greenhouse in October, 1976, produced plants that flowered in March, 1977. But the species is not an annual in the usual sense of the term. Even though they flower the first year, the plants of this species continue their growth to become woody at the base. Wild plants of S. stellatum often appear to be apetalous and it is possible that this is the case ‘of n = 8 was found in Rollins é- Roby 7490 from Coilechiaeianes Cage ec a ee 3. S. fruticulosum (Rollins) Rollins, comb. nov., based on Cibotarium fru- ticulosum Rollins, Contr. Dudley Herb. 3: 187. 1941. SPECIMENS STUDIED. Mexico. San Luis Potosi: Minas de San Rafael, Purpus 5374 (cH, holotype; NY, US, MEXU, isotypes); same oe ——- 5235° (uc); ca. 12 km. al SE de Sphaerocardamum 15 4. S. macrum (Standley) Rollins, comb. nov., based on Lepidium macrum Standley, Field Mus. Nat. Hist. (Bot.) 17: 248. 1937. Cibotarium — ih aremccand th —s — Dudley Herb. 3: 189. 1941. SPECIMEN: oth olanaapr : 16 mi. S$ o} eaga, Kenoyer & Crum 2807 ae Nue e San oak emt Sanctus ap Recon” Municipio de Derrumbadero Mueller 2411 fee isotype). 5. S. ramosum Rollins, sp. nov. Herba nnis; caulibus divaricato-ramosis, ca. 2 dm. altis, dense foliatis, pubescentibus; foliis pe RR tiny sparse denticulatis, dense pubescentibus, sessilibus, 1-4 cm. longis, 4-8 talis albis, spathulati i ngis; stylis ca. 1 mm. longis; Joculis 4-6 ovulatis; seminibus ca. 1 mm. lon cotyledonibus incumbentibus Holotype in iatp ray Herbarium, collected in Nuevo Leon on the east slope of Cerro Potosi at ca. 6050 ft , dry open places in a waste area between corn ay July 9, 1963, R. L. McGregor, L. ri greed: A. J. Robinson, R. del Rosario & R. § Perennial, erect, leafy, ca. 2 dm. tall, densely nate throughout; trichomes dendritic; stems virgately branched and with a densely flowering inflorescence terminating each branch; leaves all cauline, sessile, oblanceo- late, sparsely denticulate, 1-4 cm. long, 4-8 mm. wide; sepals oblong, non- saccate, hyaline-margined, 1 mm. long or slightly more; petals white, spa- tulate, 1.5 to nearly 2 mm. long; claw very narrow at point of insertion; fruiting pedicels spreading at = angles to rachis, slender, straight, 5-8 mm. long; siliques obovate, truncate at base of style, 3-4 mm. long; valves moderately keeled on back; styles glabrous, ca. 1 mm. long, 4-6 ovules in each loculus; seeds plump, marginless, ca. 1 mm. long; cotyledons incumbent. The siliques of Sphaerocardamum ramosum are much like those of S. macrum but the petals of that species are minute, being 1 mm. or less long with scarcely any expansion in the blade area whereas the petals of S. ramo- sum are comparatively conspicuous, ranging up to 2 mm. in length and with an expanded blade. The leaves of $. ramosum are all denticulate while those of S. macrum are nearly all entire. Branching begins near the base in S. ramosum but in $. macrum branching occurs near the top of the stems. Like several other species of Sphaerocardamum, there are trichomes present on the interior of the valves in $. ramosum. The type collection is the only one known of this species. 6. S. compressum Rollins, comb. nov. et stat. nov., based on Cibotarium divaricatum var. compressum Rollins, Contr. Dudley Herb. 3: 180. 1941. SPECIMENS STUDIED. Mexico. Coahuila: Sierra de Parras, Purpus 4603 (Gx, holotype). The strongly compressed siliques in this species result in a very narrow replum which has an acute angle at the ape and the valves are strongly keeled on the back. This is quit st to the situation in S. divaricatum where the replum akong with an tse ae atthe apex and the vas are rounded on the back. The pubescence of S. §. divaricatum is so dense that 16 Reed C. Rollins the plants are canescent whereas the evenly spaced trichomes on plants of S. compressum, particularly on the siliques, provide only a grayish to green- ish aspect. The interior of the valves are glabrous in S. compressum while these surfaces are covered with trichomes in S. divaricatum. These differ- ences support the elevation of the taxon I treated earlier as a variety to the rank of species. 7. §. divaricatum (Rollins) Rollins, comb. nov., ony on Cibotarium divar- icatum Rollins, Contr. Dudley Herb. 3: 189. 1 IMENS STUDIED. Mexico. Coahuila: Sierra de Parras, hee 1027 (GH, holotype; Ny, typ Saltillo, Palmer 347 (GH, Ny, UC, US); La Casita, Kenoyer ¢¢ Crum 3067 (cH). Hidalgo: E] Capulin, between Actopan and Ixmiquilpan, Moore & Wood 4253a (GH); same locality, Oct. 17, 1983, Rollins et al. 83347 (cu). 8. S. macropetalum (Rollins) Rollins, comb. nov., based on Cibotarium macropetalum Rollins, Contr. Dudley Herb. 3: 190. 1941. SPECIMENS STUDIED. Mexico. Coahuila: Carneros Pass, Pringle 2848 (Gu), Pringle 3195 (GH, NY, UC, US); 12 mi. E of Saltillo, Rollins & Tryon 58139 (GH); 59 km. $ of Saltillo, Stanford et al. 290 (GH); 29 mi. S of Saltillo, Rollins & Roby 7489 (Gu); 26 mi. S of Saltillo, Rollins ¢> Tryon Mpio. de Charcas, 10-IX-55, J. Rzedowski 6551 | (ENCE). Zacatecas: Puert o de Rocamontes, M. c. — 10487 (on MEXU); 1.5 Snot g ion d 100, Concepcion del Oro, Palmer i be icv NY, UC, S, isotypes); same locality, pao 17399 (GH); ca. 16 a mi. Concepcion del Oro, ncnzace 13289 (cH); 9.6 mi. W of Concepcion del Oro, Rollins A pee 74137 (ENCB, GH). As is evident a the number of specimen citations, Sphaerocardamum macropetalum is the best known species of the genus. It often grows in the same locations as S$. stellatum and was confused with that species by Watson (1890). However, the two species are amply distinct and can be readil recognized in the field. In the two — where I have observed them, there is no evidence of hybridization. The chromosome number of $. macropetal- um is n = 8 (Rollins & Riidenberg, 1977). ACKNOWLEDGMENTS It is a pleasure to financial t from th rovi : ae Agar acknowledge support e Roads Grant, provided by Mrs. Sphaerocardamum 17 LITERATURE CITED segue R. C. 1941. Some generic relatives of Capsella. Contr.. Dudley Herb. 3: 185-191. Miscellaneous Cruciferae of Mexico and western Texas. Rhodora 59: 61-71. AND LILy RUDENBERG. 1977. Chromosome numbers of Cruciferae III. Contr. Gray Herb. ~ 207: 101-116. SCHAUER, S. 1848. In C. G. Nees & S. — — _ age pits taay Generum Novorum -ageneae Plantarum i in Terris M canis Cres 20: 720-21 SCHULZ, O. E g 1A der Cruciferen. Bot. Jahrb. Syst 66: 91-102. . 1936. Cruciferae. In Engler & Harms, Nat. Pflanzenfam. ed. 2 17b:(227]-658, fig. 415 O-W. Watson, S. 18go. Contributions to American botany IX. Proc. Amer. Acad. Arts 25: 124-163. EC USEF, contributions from the oe wat Gray Herbarium of Harvard University — No. 214 November 1984 Harvard University, Cambridge, Massachusetts | | ; Reed C. Rollins | Studies in the Cruciferae of Western North America II | : | | ' Reed C. Rollins | Studies on Mexican Cruciferae II | DSP gv Zac yh PRR BRN A i ce oh ih avo aah shay os tf Reed C. Rollins Studies in the Cruciferae of Western North America II Reed C. Rollins | Studies on Mexican Cruciferae I! Published by THE GRAY HERBARIUM OF HARVARD UNIVERSITY ISSN: 0195-6094 Issued November 15, 1984 STUDIES IN THE CRUCIFERAE OF WESTERN NORTH AMERICA II! REED C. ROLLINS Stimulated by leads provided by new collections of Cruciferae from west- ern United States, we organized field trips to various sites in the states of Colorado, Idaho, Montana, Nevada, Utah, and Wyoming. The purpose was to study populations of various species in the field and to collect for laboratory analysis samples of little known or undescribed taxa. The results of these combined studies, including those on materials from other sources, are incorporated in the pages that follow. These include the presentation of new entities in the genera Arabis, Descurainia, Draba, Lesquerella, Physaria, and Thlaspi. ARABIS A very dense and fine vesture producing a hoary appearance on leaves, stems, and fruits is characteristic of several species of Arabis, particularly some of those of arid areas. Such species as A. puberula Nuttall, A. pulchra M. E. Jones var. pulchra, and A. subpinnatifida S. Watson meet these specifications. All three of these species have reflexed or pendent siliques. Undescribed plants from Montana fit i so ina me group of species as far as trichome type, density, and oncerned, but they have ascending rather than ‘descending siliques. In searching for a related species to the Montana plants, which I am calling A. fecunda, the hoary plants of A. shockleyi Munz need to be considered. However, the siliques of that species, while ascending, are glabrous rather than densely pubescent. Also, the siliques are curved outwardly rather than being straight as in A. fecunda. A better candidate for a close relationship is A. fernaldiana Rollins even though the indument is not so dense and the plants as hoary as in the other species mentioned. It is with the latter that the new species is com- pared below. / Arghis fecunde Rollins, sp. nov. ovate Saf dd Ma docs acti, Ra ime week eo cee dim: ; foliis radicalibus petiolatis, spathulatis vel lineari-oblanceolatis, integris vel sparse Sas Lh i is; , nonsaccatis, dense Sas an kus ik ee oe 9-13 mm longis, 3-5 mm latis; fructiferis erectis vel parce divaricatis, rectis, 6-10 mm longis; siliquis erectis, rectis vel parce curvatis, 3-5 cm longis, ca. 1.5 mm latis; stylis ca. 1 mm longis; seminibus uinseriatis, subor- i , anguste-alatis, ca. 1 di ledonib . of the University of Montana. Montana. By nyagpedes apse — er apgeagr Jaculyn Cory 1611. ee we 'The first paper 491-510. 1983. 2 REED C. ROLLINS Perennial with a simple or branched caudex, densely pubescent through- out with fine dendritically branched trichomes; stems erect to somewhat decumbent at base, simple or few branched, 1-3 dm high; leaves hoary, dimorphic; basal leaves petiolate, spatulate to linear oblanceolate, entire or with a few broad teeth in the blade area, 1-3 cm long, 2-4 mm wide; cauline leaves sessile, entire or the lower with a few teeth, oblong, acute, sparingly auriculate to nonauriculate, 7-20 mm long; inflorescences usually congested; sepals oblong, nonsaccate, densely pubescent, 6-7 mm long, ca. 2 mm wide; petals purplish, obovate, not unguiculate, narrowing gradually from blade to point of insertion, 9-13 mm long, 3-5 mm wide; fruiting pedicels erect to slightly divaricately ascending, straight, 6-10 mm long; siliques erect, con- gested, usually appressed to rachis, straight to slightly curved inward, 3-5 cm long, ca. 1.5 mm wide, valves densely pubescent, compressed between seeds; styles ca. 1 mm long; seeds in a single row, suborbicular to slightly longer than broad, narrowly wing-margined all around, ca. 1.2 mm in diame- ter, mucilaginous when wetted; cotyledons accumbent. SPECIMENS STUDIED. Montana. Ravalli Co.: dry open slope, game range NE of Ham- ilton, May 17, 1975, Cory 1416 (MoNTU). Most of the stem length is given over to silique production in Arabis fecunda, hence the specific name. In general habit, the plants of this species resemble those of A. fernaldiana. However, A. fernaldiana has an openly branched caudex which is borne mostly above ground while the caudex branching of A. fecunda is very tight and is below ground level. The siliques of A. fernaldiana are in loose racemes and they are divaricately ascending, but those of A. fecunda are congested, erect or nearly so, and appressed to the rachis. The seeds of these two species are different. Those of A. fecunda are consistently winged all around while those of A. fernaldiana are either wingless or imperfectly winged, mostly with a narrow wing on the distal margin. Another difference is in the radical leaves. In A. fernaldiana the radical leaves are all similar, but in A. fecunda, after fruiting occurs, new tufts of leaves are produced that are different from the earlier ones. The oldest leaves are spatulate and short-petioled while the newer tufts of leaves are -oblanceolate and long-petioled. A similar sequence of leaf form is characteristic of A. subpinnatifida and h Ips distinguish that species from A. puberula. DESCURAINIA _ As pointed out by Detling (1939), branching in plants of the native Amer- ican species of Descurainia is primarily of two kinds. In one, exemplified by D. richardsonii (Sweet) Schulz, the central axis is well-developed, resulting in tall plants with relatively short branches. The second still has a central continue upward. These, although shorter than the main axis in most CRUCIFERAE OF WESTERN NORTH AMERICA 3 instances, provide a wider and more bushy branching system than the first : e latter, exemplified by D. pinnata (Walter) Britton, there are substantial internodes on the main axis between the branches. A third branching type, found in D. torulosa Rollins where the branches arise at the crown of the caudex and are decumbent, was recently recognized among North American species (Rollins, 1983). A fourth branching habit, where all branches arise at or near the base of the plant, characterizes a new species, D. ramosissima, which is described below. Here there are very short inter- nodes between the bases of each of the numerous branches which are all nearly the same length on each plant. The central axis is so short that it is hardly recognizable as such and the resulting growth form is bushy. Some plants of D. pinnata subsp. ochroleuca (Wooton) Detling approach this growth form. penne ramosissima Rollins, sp. nov. erba annua, ramosissima, 1.5-3 dm alta, plus minusve virida, dense pubescentibus; tri- ‘saints dendritics; foliis bipinnatis, 2-4 cm longis, 1-1.5 cm latis, lobatis obtusis; sepalis oblongis, nonsaccatis, 1.5-1.8 mm longis, sparse pubescentibus; petalis — flavis, 1.7- 2 mm longis; infructescentiis elongatis, rachis glandulosis; pedicellis div: rectis, filifor- mibus, _ Sparse Vapors ze 6-10 cm longis; siliquis prope teretibus, grees sp ange oblongis, glabris, 7-10 mm longis; loculis 10-16 ovulatis; seminbus oblongis, crassis, bentibus. Holotype int the Gray Herbarium. Colorado. Saguache Co.: on sandy soil of an open plain, near State Route 17, 7 miles § of Villa Grove, Aa 16, 1983, Reed C. & Kathryn W. Rollins . Isotypes to be uted. Annual, icasty and intricately aad from near base, bushy, greenish, 1.5-3 dm tall; foliage and branches densely pubescent with dendritically branched trichomes but not canescent, nonglandular except on rachis of infructescences and pedicel bases; branches about the same length, leafy; leaves bipinnate, 2-4 cm long, 1-1.5 cm wide, scarcely reduced upward, primary divisions cut to a narrow rachis, ultimate lobes oblong to nearly linear, obtuse; inflorescences dense, elongating in fruit; sepals oblong, pur- plish to yellowish, nonsaccate, 1.5-1.8 mm long, 1 mm or less wide, pubes- cent with a few simple or forked trichomes; petals creamy yellow, spreading at anthesis but not unguiculate, spatulate, narrowing gradually to point of insertion, rounded at apex, 1.7-2 mm long, less than 1 mm wide; stamens excerted; filaments not dilated, ca. 1.5 mm long; anthers oval, ca. 0.5 mm long; infructescence axis densely glandular above, with a mixture of glands and other trichomes below; fruiting pedicels divaricately ascending, filiform, straight, 6-10 mm long, sparsely pubescent with simple, kocked, and den- fkchi ase te aks ‘dildos 1.5 mm wide; A cata io D2 om long; ovules 10-16 in each locule; seeds oblong, plump, reddish brown, 4 REED C. ROLLINS wingless, ca. 1 mm long, ca. 0.6 mm wide, in a double row at center of silique and single row at each end; seed coat reticulate-foveate; cotyledons incumbent. In the arid parts of western North America, Descurainia is one of the most commonly encountered genera of the Cruciferae. I have studied and col- lected various species of the genus many times but have never encountered two native species growing together except where D. ramosissima was found. There D. pinnata subsp. halictorum (Cockerell) Detling was growing in even greater abundance than D. ramosissima, and the two taxa were intermixed over a wide area. This does not hold for the introduced D. sophia (L.) Webb, which has been seen intermixed with native species several times. Aside from their growth form, which is very different as indicated above, subsp. halictorum was easily distinguished because of its gray foliage compared to the greenish foliage of D. ramosissima. I looked for, but did not see, any evidence of hybridization between the two taxa. Silique shape in Descurainia ramosissima is somewhat intermediate between the D. richardsonii complex and the D. pinnata complex. The siliques taper in both directions, a situation that is correlated with the way the seeds are arranged. In the central portion of the silique where there is maximum width, there are two rows of seeds but these taper out to one row toward each end. DRABA Endemism in the mountainous area of north central Idaho is well estab- lished in the genus Draba. Such species as Draba argyrea Rydberg. D. hitchcockii Rollins, D. oreibata Macbride & Payson, and D. sphaerocarpa Macbride & Payson are known only from that region, and there are a number of other species that incorporate this area in their geographical ranges: Draba densifolia Nuttall, D. loncocarpa Rydberg, D. oligosperma Hooker, D. sonii Macbride var. treleasii (Schulz) C. L. Hitchcock, and D. praealta Greene. Now another endemic to this area has been discovered and it turns out to be an undescribed species. It was found in the same place as Thlaspi aileeniae, another new species described elsewhere in this publication. Draba trichocarpa Rollins, sp. nov uh : . per Pp . 4: -h . : + oe - iL r t 31 : 1-3 cm longis, ise pubescentibus; tri iticis; foliis rosulatis, oblongis vel spathulatis, non- petiolatis, integris, 2-3 mm longis, 1-1.5 mm latis; sepalis obovatis, nonsaccatis, pubescentibus, 2.5-3 mm longis, ca. 2 mm latis; 2.5-3.5 mm longis, 2.2-2.8 mm latis, laminiis vel ribus; iferi i s, 2-3 mm longis amini vatis vel orbi ; pedicellis fructiferis rectis, siliquis ovatis, compressis, dense pubescentibus, 2.5-4 mm longis, 2-3 mm : : mm longis; seminibus crassis, exalatis, oblongis vel anguste-ovalis, 1.8-2 mm longis; ca. 1.2 mm CRUCIFERAE OF WESTERN NORTH AMERICA 5 Perennial, caespitose, clumps up to 10 cm across; caudex profusel branched, dense, covered with old leaves and leaf-bases, leaves densely rosulate, entire, oblong to spatulate, obtuse, 2-3 mm long, 1-1.5 mm wide, pubescent with coarse dendritic or forked trichomes, simple trichomes often present on margins toward leaf-base, trichomes crooked, dendritic ones usually branched near apex; fruiting stems scapose, erect, densely covered with coarse dendritically branched trichomes, 1-3 cm long including infruc- tescences; sepals obovate, nonsaccate, hyaline margined, pubescent, 2.5-3 mm long, ca. 2 mm wide; petals 2.5-3.5 mm long, 2.2-2.8 mm wide, blade nearly orbicular to broadly obovate, narrowed abruptly to a short claw less than 1 mm long; filaments 1-1.5 mm long, dilated at base; anthers oval, less than 1 mm long; fruiting pedicels divaricately ascending, straight, densely pubescent, 2-3 mm long; siliques ovate, flattened toward apex, densely covered with dendritic trichomes, 2.5-4 mm long, 2-3 mm wide; styles ca. 0.5 mm long; seeds plump, oblong to narrowly oval, wingless, 1.8-2 mm long, ca. 1.2 mm wide; ovules 2-4 in each locule; cotyledons accumbent. The dense clumps of Draba trichocarpa show very much the same habit of growth as D. paysonii Macbride var. treleasii (Schulz) C. L. Hitchcock, a species of somewhat higher altitudes. These taxa differ especially in the types and mixtures of trichomes that occur on different parts of the plants. Large simple or forked trichomes predominate in var. treleasii while smaller dendritically branched trichomes are mostly present in D. trichocarpa. In the latter, the dendritic trichomes are erect on the fruits, pedicels, and scapes and under magnification give the appearance of a dense forest in miniature. Individual trichomes are branched primarily toward the top of a pemnerit long : stalk. The bapaenaee is somewhat different on the leaves whoce os cae n the leaf. forked ones are on th sniaigia: Petal color is not determinable on she material at er lesmuse only dessicated flower parts were available for study. However, because of the similarities in petal fading seen in var. treleasii, it is reasonably certain the petals of D. trichocarpa are yellow. Mulligan (1971) pointed to Draba paysonii, D. ruaxes Payson & St. John, and D. ventosa Gray as being a related scapose yellow-flowered group of species. Of these, D. ruaxes and D. ventosa are most closely related to each other and are quite unlike D. paysonii s.l. in growth form and pubescence, as well as basic chromosome number. As suggested above, it is to D. paysonii and particularly var. treleasii that D. trichocarpa is to be compared as far as habit is concerned but the trichomes, especially on the scapes, pedicels, and fruits, are more like those of D. ventosa than of D. paysonii var. treleasii. ” Draba daviesiae (C. L. Hitchcock) Rollins, stat. nov. pet De ee ran ake L. Hitche. =o Cronquist, ; to Saxi- ae 489. Univ. of Wash. Press, Seattle, 1964. D. Dee ee dander Hitche.) Welsh & Reveal, Great Basin Nat. 37: 320, 1977. 6 REED C. ROLLINS SPECIMENS STUDIED. Montana. Ravalli Co. Bitterroot Mts.: Base Peak Ridge, 12 Aug. 1967, Lackschewitz & Fageraas 288 (MONTU); Bitterroot divide above Duffy Lake, 4 July 1977, Lesica 76 (MONTU); Heavenly Twins, 15 Aug. 1971, Lackschewitz 3287 (MoNTU); Pyramid Butte, 24 Aug. 1968, Lackschewitz & Fageraas 941 (MONTU); St. Joseph Peak, 8 Aug. 1966, Lackschewitz 7 July 1965, Pemble 307 (MonTU); talus above St. Mary’s Lake, 10 Muhlick iti ies denser of St. Mary's Peak, 17 July 1983, Rollins ¢> Rollins 83304 with itz & Fageraas 103 (MONTU); Trapper Peak, 25 July 1964, Pemble & Harvey 40, 47 (MonTU): same locality, 9 July 1966, Lackschewitz & Fageraas 10 (MONTU). Having collected the rare Draba apiculata on three separate occasions in northwestern Wyoming (Rollins ¢¢ Munoz 2839 in 1939: Rollins ¢> Porter 51272 in 1951; and R. C. & K. W. Rollins 83320 in 1983), I was struck with the very different habit of growth of what Hitchcock (1964) called D. apiculata var. daviesiae when I saw it at the type locality on the summit of St. Mary’s Peak in the Bitterrot Mountains of southwestern Montana. The matted, loosely branching caudex with elongated leafy branches was quite in contrast to the dense rosulate caudex structure of D. apiculata and the leaves, instead of being acute and apiculate with simple trichomes (as in D. apiculata), were rounded at the apex with a fringe of marginal simple trichomes, but no apiculation. As indicated by Hitchcock (1964), the scapes are longer, with 5- 10 flowers instead of 2-5 flowers, the pedicels are longer, and the leaves are larger in var. daviesiae than in var. apiculata. The differences are so out- standing that these taxa cannot be reasonably considered varieties of the same species and I have, therefore, elevated var. daviesiae to the rank of species. I cannot agree with Welsh and Reveal (1977) that Draba apiculata C. L. Hitchcock, “is a poorly differentiated phase. . . ” of D. densifolia. It appears to me that Hitchcock (1941) included too much in D. apiculata and thereby picked up material I would refer questionably to D. densifolia. But if D. apiculata is restricted to plants agreeing with the type, the species is com- prehensible and readily distinguished from D. densifolia. The densifolia-like plants need further study. They occur on St. Mary's Peak at the type locality of D. daviesiae, but they are easily distinguished from that species. pe , dense pubescentibus; icibus ramulosis, stramineis foliis fasciculatis, oblongis vel is, cuneatis, integris, 5-8 mm longis, 2-3 mm latis: foliis simplicibus, 4-7 em longis; 2.5-3 mm longis, ca. 1.5 mm latis; is, 4-5 mm longis, ca. 2 mm latis; pedicellis ris rectis, 4-6(-8) mm longis; siliquis late elliptici is, dense pubescenti- bus, 4.5-5.5 mm longis, 3.5-4 mm ; styllis plus minusve 1 mm longis; loculis 4-5 ovulatis: seminibus oblongis ‘ is, ca. 2 mm longis, ca. 1.2 is; cotyledonibus accum- us. Holotype in the herbarium of the Missouri Botanical Garden. Utah. Beaver Co.: on loose calcareous talus, E slopes, peak and saddle, Tushar (Belknap) Peak, Tushar Mts., 11,500-12,000 ft., July 22, 1940, Bassett Maguire 19778. Isotype and of holotype cu. CRUCIFERAE OF WESTERN NORTH AMERICA ca Perennial, loosely matted, densely pubescent throughout with fine den- dritically branched trichomes, both sterile and fertile active shoots present; creeping rootstocks highly ramified, stramineus; leaves monomorphic; tufted leaves in small elongated clusters, oblong to narrowly obovate, nonpetiolate, entire, cuneate at base, obtuse to acute at apex, 5-8 mm long, 2-3 mm wide; cauline leaves both below and above tufts, those on fertile stems 4-8, mostly toward base, uppermost usually subtending pedicels; fertile stems simple, 4-7 cm long including infructescence; sepals oblong, nonsaccate, 2.5-3 mm long, ca. 1.5 mm wide; filaments markedly dilated at base; petals obovate, gradually narrowed from blade to point of insertion, 4-5 mm long, ca. 2 mm wide; fruiting pedicels divaricately ascending, 4-6(-8) mm long; siliques broadly elliptical, compressed parallel to septum, densely pubescent, 4.5- 5.5 mm long, 3.5-4 mm wide; styles slightly less than 1 mm long; ovules 4- 5 in each locule; seeds oblong, plump, wingless, light brown, ca. 2 mm long, ca. 1.2 mm wide; cotyledons accumbent. Draba ramulosa is mostly closely related to D. ventosa Gray, which it resembles in growth form, particularly the production under appropriate conditions of numerous straw-colored creeping rootstocks, which result in a tangled mass. The elongated clusters of gray leaves are also similar although their shapes differ somewhat. Also, the two species are similar in having filaments with a dilated base, and the density of the vesture is about the same. They differ in silique shape, size of the stigmatic area, size and branch- ing of the trichomes, and in the fact that D. ventosa is scapose while D. ramulosa has leaves present on the fertile stems. The siliques of D. ramulosa are elliptical while those of D. ventosa are oval or broadly ovate to nearly orbicular. In D. ramulosa the stigmatic area, as seen on mature siliques, is the same diameter as the styles, but in D. ventosa the apex of the style flares to at least twice the diameter of the rest of the style. The trichomes of D. ramulosa are fine and more highly branched than those of D. ventosa where the pubescence must be characterized as being coarse. LESQUERELLA An uncommonly condensed habit of growth is found in certain taxa of Lesquerella and the related genus Physaria. This is indicated by the specific names L. condensata A. Nelson and P. condensata Rollins. This growth form is not only found in the Cruciferae but in a number of other plant families as well, and in the Rocky Mountain region it appears to be common where the plants grow on certain decomposed shales. These are abundant in the drainage area of the upper Colorado River and its tributaries. A new species of Lesquerella has been found in just such shale barrens of the Green River Formation in northwestern Colorado. If possible, the condensed habit is even more exaggerated in this species than in the other two mentioned. 8 REED C. ROLLINS v Lesquerella congesta Rollins, sp. nov. Herba perennis, congesta, 1-3 cm diam, d pub tibus; trich ti tellati iatis; caudicibus crassis, simplicibus vel sparse ramosis; caulibus 0.5-1.5 cm longis; foliis basalibus integris, erectis, lineari-oblanceolatis, nonpetiolatis tis vel anguste obtusis, (6-)8-12(-15) mm longis, 2-3 mm latis; pedicellis fructiferis erectis, 3-6 mm longis; siliquis ovatis, erectis, 3.5-4.5 mm longis, 2.5-3.5 mm latis; stylis 1-1.5 mm longis; loculis 2-ovulatis; seminibus ovoideis vel prope orbicularibus, noncompressis, ca. 2.5 mm longis; cotyledonibus accumbentibus; floribus ignotis. TI. Holotype in the Gray Herbarium. Colorado. Rio Blanco Co.: near top of ridge, decomposed Gulch and Piceance Creek, T2S, R9TW, Sec. 4, June 20, 1983, Reed C. & Kathryn W. Rollins 8394 with Scott Peterson, Aileen G. Roads, Karen Wiley-Eberle & Dieter Wilken. Isotypes to be distributed. Perennial with a thick caudex and long thick taproot; caudex simple or rarely few branched below ground, covered with old leaf-bases and leaf- scars; infructescenes nearly sessile or fruiting stems up to 1.5 cm long; plants 1-3 cm in diameter, densely pubescent with appressed stellate trichomes; trichomes stiff, radiately branched, primary branches 4-5, fused at center, ultimate tips 18-25; leaves silvery, monomorphic, basal erect, linear-oblan- ceolate, entire, acute to narrowly obtuse, without a distinct petiole, (6-)8-13 (-15) mm long, 2-3 mm wide; cauline leaves 1-3 per stem, similar to basal: fruiting pedicels erect or nearly so, straight to slightly curved, 3-6 mm long; siliques erect, ovate, flattened at apex and along margins, densely pubescent with appressed trichomes, 3.5-4.5 mm long, 2.5-3.5 mm wide: styles 1-1.5 mm long; replum ovate, acute; septum entire or with a small perforation; valves glabrous on interior; ovules 2 in each locule: seeds plump, wingless, ovoid to nearly orbicular, ca. 2.5 mm long; mucilaginous when wetted: cotyledons accumbent, radical equalling cotyledons. Flowers not known. OTHER SPECIMENS STUDIED. Colorado. Rio Blanco Co.: 1.5 miles E of junction of Little Duck Creek and Trail Canyon, T1S, ROTW, S7, 2 June 1982, Walker, Waters ¢> Riefler 82-108 Pi iles W! n ree Yellow Creek Road, T1S, R98W, $7, 19 May 1982, Walker ¢ Sigstedt 82031 (cs); North Dudley ulch, ca. Ys mile has junction of North Dudley Gulch and Piceance Creek, T2S, R97W, $4, Ni We were alerted to the novelty of Lesquerella congesta, not only by the growth habit, but more importantly by the nature of the trichomes. These are less than one-half the size of those of the related L. alpina s.1., the rays are shorter, more massive, and are more fused toward their bases than those of L. alpina, where the rays are mostly free with relatively long arms. Although L. condensata and L. congesta are fairly close in their habit of growth, their trichomes are even more different from each other than those of L. alpina and L. : Compared to most variants of Lesquerella alpina, L. congesta has much shorter styles, 1-1.5 mm vs. 1.5-6 mm. It is true that in some specimens of L. alpina, the style length of L. congesta is approached, but there is very CRUCIFERAE OF WESTERN NORTH AMERICA 9 little overlap from the species as a whole. Also, the margins of the siliques of L. congesta, as well as the apex, are flattened whereas the flattening is confined to the apex in L. alpina. Lesquerella humilis Rollins, sp. nov. Herba perennis, dense pubescentibus, argentea; caudicibus crassis, plerumque simplicibus; trichomatibus stellatis, ramosis; caulibus prostratis, simplicibus, 2-5 cm —— radicalibus petiolatis, integris, (1-)1.5-2.5(-3) cm longis, laminis ellipticis vel late obovatis, 3-6(-7) mm letis, 4-7 mm longis; foliis caulinis 3-6, spathulatis, 3-7 mm longis; sepalis oblongis, vases pubescen- tibus, 4-5 mm longis, 1.5-2 mm latis; petals spathu ats, retusis, 7-8.5 mm 3-3.5 mm latis; pedicellis fructiferis rectis vel plus , 3-4 mm longis; silliquis compressis, 3-4 mm altis, 4-5 mm latis; stylis 2-3 mm longis; loculis 2-ovulatis; seminibus crassis, semior- ——. exalatis, ca. 2 mm longis; cotyledonibus accumbentibus in the Cry Herbarium. Montana. Ravalli Co.: on steep hillside of metamorphosed ce and detritus, approach to and near summit of St. Mary’s Peak, Bitterroot Range, July 17, 1983, Reed C. & Kathryn W. Rollins 83300, with Klaus H. Lackschewitz, Peter Lesica ¢ Aileen G. Roads. Sects ha baked tributed. Perennial, densely pubescent and silvery from an encrustment of stellate trichomes; primary trichome branches 5-6, free to base to slightly fused at center, forked or 3-branched, trichomes with 16-25 free ends, appressed on upper leaf surface, less appressed to somewhat flaring on lower leaf-surface; caudex usually simple, thick, covered with old leaf-bases; stems prostrate, simple, one or two to several, arising below and among a terminal rosette of leaves, 2-5 cm long; rosette leaves petiolate, entire, (1-)1.5-2.5(-3) cm long, blade elliptical to broadly ovate or obovate, usually narrowed abruptly, 3-6 (-7) mm wide, 4-7 mm long, obtuse; cauline leaves 3-6, spatulate, cuneate at base, 3-7 mm long; inflorescences 3-5 flowered, scarcely elongating in fruit; sepals yellowish, oblong, densely pubescent, 4-5 mm long, 1.5-2 mm wide, outer pair slightly saccate, inner pair non-saccate; petals yellow, spa- tulate, retuse or rarely with a deeper sinus at apex, narrowed gradually from blade to claw, 7-8.5 mm long, 3-3.5 mm wide; stamens strongly tetradyna- mous; filaments of paired stamens ca. 4 mm long, anthers ca. 1 mm long; pedicels straight to slightly curved, nearly paralleling rachis, 3-4 mm long; siliques wider than high, compressed contrary to plane of septum, shallowly notched to nearly truncate at base of style, 3-4 mm high, 4-5 mm wide, valves densely pubescent on exterior with trichomes that have ascending to erect rays, sparsely pubescent on interior; replum oval to broadly oblong, acute at apex, 2.5-3.5 mm long; septum usually folded; styles 2-3 mm long; ovules 2 in each locule; seeds plump, wingless, —: compressed, orbi- cular to semiorbicular, ca. 2 mm in diameter; cotyledons accumbent, orbi- cular or nearly so OTHER SPECIMENS STUDIED. Montana. Ravalli Co.: dry exposures, summit, St. Mary’s Peak, pe 9, 100 ft. ph 1973, Lack itz 4560 (GH Woodland ¢& Arno 077 (MonTU e and below kru same locality, June 19, 1974, Lackschewitz ¢> Scheack 4944 (cx), rocky fellcld, E St. J toiak Fok Bitterroot Mountains, July 4, 1970, 2126 (montu); dry ledge, St. J — 117 (Montv); dry S slope, same locality, July 24, 1971, Lackschewitz ¢ Gouaux s.n. (MONTU). 10 REED C. ROLLINS The distinctiveness of Lesquerella humilis rests on characters such as the few ovules and position of the funiculi in the ovary, the spreading trichome branches on the valves of the siliques, the few-flowered and non-elongating inflorescences, and the trichome pattern on the rosulate leaves. Compared to its nearest relative, L. hemiphysaria, which has 4 to 8 ovules in each locule with the funiculi extending down each side of the replum, L. humilis has 2 or sometimes but one ovule per locule and they are attached near the apex of the replum. Usually but one ovule develops resulting in a single seed in each valve. The dense covering of trichomes with their branches spreading away from the valve surfaces in L. humilis is quite in contrast to the scattered and appressed trichomes on the valve surfaces of L. hemiphysaria. In fact, the silique valves in L. hemiphysaria are sometimes glabrous or nearly so. There are usually fewer than 6 flowers on each stem of L. humilis and these mature near or at the shoot apex whereas in L. hemiphysaria there are many -flowers ultimately resulting in somewhat elongated infructescences. Although the trichomes are fairly similar in the two species, they are considerably larger and with less fused branches in L. humilis than in L. hemiphysaria. On the whole, the plants of L. hemiphysaria are larger with more numerous flowering stems and leaves than in L. humilis. As far as our present knowl- edge goes, the two species are completely allopatric, L. hemiphysaria being confined to central Utah and L. humilis to western Montana. v Lesquerella klausii Rollins, sp. nov. mm altis, ca. 5 mm latis; replis anguste-obovatis superne obtusis, 2.5-3 longis; stylis pubescentibus vel glabris, 3-3.5 mm longis; loculis 2 sane wv seminibus schestietedies Gal late oblongis, crassis, exalatis, ca. 2 mm longis, ca. 1.8 mm latis; cotyledonib bentib : Holotype in the herbarium of the Botany Department, University of Montana. Montana. pen gravel slide, W side above Hwy. 200 Pass, elev. 5,800 ft., July 25, 1982, Klaus H. Lackschewitz é David Ramsden 10112. Gaotweaan Perennial from a taproot, densely stellate pubescent: trichomes loosely spreading, primary rays 3-5, forked, ultimate rays exceptionally long for members of the genus; caudex simple, only slightly enlarged; radical leaves petiolate, entire, 1.5-2.5 cm long, blade obovate to deltate, petiole slender; cauline leaves oblanceolate to spatulate, 6-9 mm long; stems erect to decum- bent at base, slender, 6-10 cm high; infructescences loose, 1-3 cm long; pedicels slender, sigmoid, 5-7 mm long; siliques broadly obovate, slightl : ? > ‘ > ; y bilobed to nearly truncate above, densely pubescent with spreading tri- chomes, ca. 4 mm high, ca. 5 mm wide, valves pubescent on interior; replum narrowly obovate, obtuse above, 2.5-3 mm long; styles pubescent or gla- brous, 3-3.5 mm long; ovules 2 in each locule; funiculi attached near apex of CRUCIFERAE OF WESTERN NORTH AMERICA ll replum; seeds slightly longer than broad, wingless, thick, ca. 2 mm long, ca 1.8 mm wide; cotyledons accumbent. The silique shape of Lesquerella klausii is similar to that of L. cordiformis (Rollins) Rollins & Shaw, a species of Nevada, but the trichomes are not at all alike in these species and it is not believed they are particularly related. A better candidate for a related species would be L. hemiphysaria Maguire, were it not for the presence of 4-6 ovules per locule of the siliques in that species, whereas in L. klausi only 2 ovules occur in each locule. In fact, L. klausii is not easily associated as a probable relative with any other species of Lesquerella. Because of the obcordate siliques with a sinus at their style base in some plants, the species falls in a borderline between Lesquerella and Physaria, a situation earlier discussed several times (see references in Rollins & Shaw, 1973). But according to our classification, this taxon defi- nitely falls into Lesquerella rather than Physaria. The trichomes of L. klausii are not exactly matched by those of any other species of the genus (Rollins & Banerjee, 1975). Their nature and disposition provide an easy way of identifying L. klausii. The t unusually long branch- es and these are more or less erect, forming a tangled mass, rather than being flattened to the plant surface as in many species of Lesquerella. The species is named for the principal collector, Klaus H. Lackschewitz, who specializes on the high elevation flora of Montana. PHYSARIA The genus Physaria has been of special interest to me for more than forty years (Rollins, 1939). For much of this long period newly were easily accommodated in categories that were well established. But beginning with the publication of two new species by Mulligan (1966a), a number of discoveries of new taxa have been made (Rollins, 1981, 1983; Lichvar, 1983). My own intensive fieldwork in western United States, espe- cially in 1979, 1981, and 1983, has continued to uncover previously unrec- ognized species of Physaria, and new material from others has added to the total. The emerging picture of this g of a rather large number of species that are relatively restricted, either to specialized local habitats or to particular geological formations that are in turn localized in their occurrence. In addition, there are some species, for example P. acu- tifolia Rydberg, P. chambersii Rollins, and P. didymocarpa (Hooker) Gray, that are fairly widespread. The new taxa described below appear to fall into the former category. di magico - te di ibus, crassis; cau- rn saa oe Pg ate numerosissimis, 2 repoudh vol bon docs; 47 on begh, 153 coc bai, lonieas hte oy ener, hahaa 12 REED C. ROLLINS cularibus; foliis caulinis oblanceolatis, integris, acutis vel obtusis, 1.5-3 cm longis; sepalis oblon- gis vel lineari-oblongis, nonsaccatis, pes mm longis, 23 mm latis; petalis flavis, vr. vel prope spathulatis, 10-12 = song. 1 OE m lati el divar- icatis, 1-1.5 cm longis; sili didymis, infla tis; loculis semio oricularibus, 4 ovubitic: replis anguste-oblongis, 4-5 mm cooks styllis aah vel pubescentibus, 5-6 mm ack seminibus exalatis. Holotype in the Gra ray Herbarium. Utah. Duchesne on clay-like soil of a steep road-cut, off U.S. Hwy. 191, 22.5 miles SW of Duchesne, june 23, "1983, Reed C. & Kathryn W. Rollins 83117 with Aileen G. Roads Roads. Isotypes to be distributed. Perennial with a deep taproot, densely pubescent with stellate trichomes; caudex thick, usually simple; stems numerous, simple, decumbent, 1-2 dm long; radical leaves rosulate and horizontal to ascending, petiolate, repand to coarsely dentate, 4-7 cm long, 1-2.5 cm wide, blade broadly ovate to nearly orbicular; cauline leaves oblanceolate, entire, acute to obtuse, 1.5-3 cm long; sepals oblong to linear-oblong, nonsaccate, 7-9 mm long, 2-3 mm wide; petals yellow, lingulate to nearly spatulate, tapering gradually from widest place to point of insertion, slightly widened at base, not unguiculate, 10-12 mm long, 3-4 mm wide; infructescences elongated; pedicels divari- cately ascending, straight to slightly curved upward, 1-1.5 cm long; siliques didymous, inflated, valves rounded, up to 1.5 cm high in immature siliques, densely pubescent with spreading trichomes; orifices oblong, just below middle of valve faces; replum narrowly oblong, obtuse above, 4-5 mm long; styles pubescent or glabrous, 5-6 mm long; ovules 2-4 per locule; immature seeds wingless, plump, slightly longer than broad. OTHER SPECIMENS STUDIED Utah. Duchesne Co.: steep clay bank of road-cut, she — 33, Indian Canyon, 25.2 miles W of Duchesne, May 30, 1979, "Reed C. & Kathryn W 79112 (GH). The first collection of Physaria repanda was tentatively identified as P. grahamii Morton, a rare species of the Uinta Basin of northeastern Utah. But those specimens were in flower only and the possibility of a positive identification was low. The type series, which consists of 17 specimens, does not have fully matured fruits; however, the distinctive features are sufficient- ly represented to make certain the populations sampled are not P. grahamii. In the latter species, the radical leaves are pinnatifid to deeply lobed and the trichomes present have spreading rays that produce a lanate appearing surface. In contrast, the radical leaves of P. repanda are merely repand to Oe ech, fewer in number, mil do ae dhs os a a There is a marked difference in the radical leaves of these CRUCIFERAE OF WESTERN NORTH AMERICA 13 two species. Those of P. repanda are dentate to repand with a terminal lobe that is mostly wider than long whereas the radical leaves of P. acutifolia are entire and terminated by a blade which is longer than broad. v —— saximontana Rollins, sp. nov. Herba perennis; caudicibus crassis, integris; caulibus prostratis, vel decumbentibus, 3-10 cm baie foliis radicalibus rosulatis, argenteis, petiolatis, obtusis, 1.5-3 cm lon ongis,, hain mm latis, laminis orbicularibus vel late obovatis; foliis ara = spathulatis v we integris, 1-1.5 cm longis; pedice eris 6-10 mm aati siliquis bilobatis, inflatis; loculis sori ie 3.54. ey mm nant sind ma ovalis vel late frat ca. 3mm go ca. ora -* sa tis; aa Spooks accumbentibus. Holotype in Herbarium n red soil near State Route 28, is 4 miles SW of eats Oe June 20, Pls haat bf es prertane Ww. Rollins 81374. Isotypes to distributed. Perennial with a taproot and usually simple caudex, silvery pubescent throughout; trichomes stellate with forked rays; stems several to numerous, prostrate to decumbent, 3-10 cm long; radical leaves rosulate, eed pubescent with appressed trichomes, petiolate, 1.5-3 cm long, 8-14 m wide, petiole winged, blade orbicular to broadly obovate, ahd: fear or with broad obscure tooth-like angles on each side at apex; cauline leaves broadly spatulate to linear-oblanceolate, entire, 1-1.5 cm long; sepals nar- rowly oblong, non-saccate, 5-6 mm long; petals yellow, spatulate, not ungui- culate, 8-10 mm long, 2-3 mm wide, tapering gradually from apex to point of insertion; infructescences condensed, subumbellate to slightly more elon- gated; fruiting pedicels divaricately ascending, straight to slightly curved, 6- 10 mm long; siliques deeply bilobed, inflated at maturity, sinus absent below, deep above, valves irregular, rounded, densely pubescent with spreading trichomes, shed with seed enclosed; orifice narrowly ovate to elliptical, margined with spreading trichomes, situat of valve inner face; replum narrowly ovate to broadly oblong, acute to obtuse above, not nar- rowed at middle, 3-4 mm long, 1.5-2 mm wide; styles 3-5(-7) mm long; ovules 2 in each locule (2-4 in var. dentata); funiculi near apex of replum; seeds oval to broadly oblong, wingless, slightly compressed, smooth, ca. 3 mm long, ca. 2 mm wide; cotyledons accumbent. KEY TO VARIETIES Radical leaves entire; styles 1-2 times or less length of replum var. saximontana. Radical leaves with broad teeth at gi 1 angled at apex; styles 3 or more times length of replum var. dentata. ’ Physaria saximontana Rollins var. saximontana OTHER SPECIMENS STUDIED. Wyoming. Fremont Co.: 15 mi. NW of Fort Washakie, July 22, 1983, R.C. & K.W. Rollins 83330 with Aileen Roads (c H); ca. 25 mi. NW of Morton, Wind er Indian Reservation, June 22, 1981, R.C. & K.W. Rollins 81386 (Gu); near State Route 28, 18.4 miles SW of Lander, July 22, 1983, B.C. & K.W. Selina 8900) with 4 Aileen Roads (cu). Co.: 6 miles S$ of Douglas, July 10 1951, Porter 5727 (cx). Northwestern Wyoming, 1873, C. C. Parry 25 (cH). 14 REED C. ROLLINS ¥ P. saximontana var. dentata Rollins, var. nov. Foliis radicalibus late dentatis; stylis 5-7 mm longis. Holotype in the Gray Herbarium. Montana. Lewis and Clark Co.: on upper E mo of mountain S of Solk Lake, elev. 8,100 ft., Bob Pings finns SE % Sec. 31, T24N RLIW, pi 1979, Klaus H. Lackschewitz 91 OTHER SPECIMENS Montana. G! ana gee Mountain, Glacier National Park, 9 Aug. 1964, Hervey ra ig-ssans 7213 (MONTU). Park Co.: mountain N of Sunlight Lake, Crazy Mountains, July 30, 1980, Lackschewitz 9374 (MONTU). For several years I have been encountering populations of Physaria with many of the features of P. didymocarpa, but with a number of distinctive characters that make them difficult to accept as part of that species. These populations occur southeast of the Wind River Mountains of west central Wyoming, and extend northward through the main chains of the central Rocky Mountains of Montana. The area overlaps, but is mostly to the south of, the primary geographical range of P. didymocarpa, which is largely in Canada and western Montana (Mulligan, 1967). The most significant differ- ences between P. didymocarpa and P. saximontana are in the silique shape and in the position of the orifice on the inner face of each valve. The siliques of P. didymocarpa are cordate at the base because the valves produce a narrow sinus at the base of the replum. This is well shown in the illustrations provided with the original publication of the species (Hooker, 1830). On the other hand, the siliques of P. saximontana have no sinus at their base. Here, the replum is attached at the very base of the valves and the orifice to each valve is also at the base. But in P. didymocarpa the valve orifice is near the middle of each valve face. The stellate trichomes on Physaria saximontana are not uniform over the entire plant as they are in many species of the genus. Those of the radical leaves have 6 to 8 primary rays, each of which is forked, providing 12-16 free ends. There is some > fusion of the rays at the center. These trichomes are in Itiple layers and the leaf surface. The most different from these trichomes are those on the valves of the siliques. Here, the primary rays are only 3 to 5, and by forking they produce 6 to 10 free ends which spread away from the valve surfaces. The young ovaries are covered by a tangle of spreading trichomes, appearing downy in much the same way as in P. didymocarpa. The primary rays of the silique trichomes are free to the center. Physaris stylosa Rollins, Sp. one Ribotaip st amtie-e eaesieir ogres i : E argenteis 4 cm longis, °10 mi is cans Ine i nonsaccatis, lineari-oblongis, 6-7 mim longis, ca. 1.5 mm latis; petalis spathulatis, flavis, 9-11 mm longis; tbs: replooblongo, 1.5.2 mm long: syle 69 latis; seminib s semiorbicularibus, ca. 2.5 mm diam; cotyled CRUCIFERAE OF WESTERN NORTH AMERICA 15 Holotype in the Gray Herbarium. Utah. Wasatch Co.: in sandy rocky ground of steep raw slopes with a south exposure, Duchesne Ridge above Corral Hollow, West Fork of Duchesne River, 23 miles from Tabiona, 9,800 ft. elev., Aug. 5, 1980, S. Goodrich 14905. Perennial; caudex usually branched; stems slender, prostrate to ascending, 3-8 cm long; radical leaves entire to shallowly sinuate, densely pubescent, silvery, 2-4 cm long, 5-10 mm wide, blade obovate to elliptical, petiole slender, 1-2 cm long; cauline leaves few, linear-oblanceolate, entire; leaf trichomes stellate, appressed in several layers, primary rays 8-10, forked, secondary rays 16-20; sepals non-saccate, linear-oblong, 6-7 mm long, ca. 1.5 mm wide; petals yellow, spatulate, tapering gradually from blade to claw, 9- 11 mm long, 2-3 mm wide; fruiting pedicels divaricately ascending, 7-10 mm long; siliques pubescent, with a deep sinus above and none below; valves asymmetrical, concave on outer surface, tapered on upper part toward ori- fice, 5-7 mm high; orifice at base of valve, oblong, 1.5-2 mm long; replum oblong, rounded at apex; styles slender, 6-9 mm long; ovules 2 in each locule; funiculi at apex of replum; seeds plump, nearly orbicular in outline, wingless, ca. 2.5 mm in diameter; cotyledons accumbent. Among those species of Physaria with no sinuses at the base of their siliques, P. stylosa is distinctive in having small valves that are tapered toward the orifice, very long slender styles well excerted above the valves and a branched caudex that appears to be a regular feature of the species. The tapered valves fit to a very short replum so that the length ratio of replum to style is roughly 1 to 4 where in most species of Physaria the ratio is less than 1 to 2. The silique shape is somewhat like that of P. alpina in that the valves are strongly tapered but in the latter the tapering occurs both above and below the orifice whereas in P. stylosa the tapering is all above the orifice. . the radical leaf cluster. The radical leaves of P. vitulifera are lobed or sinuate- dentate to dentate and the largest are up to 3 cm wide, while those of P. stylosa are mostly entire with the largest scarcely reaching 1 cm in width. In P. stylosa the fruiting pedicels are straight or nearly so, but those of P. vitulifera are definitely sigmoid. In the latter, the valves of the siliques are rigid and uneven whereas those of P. stylosa are smooth and papery. Tri- chomes on the valve surfaces are erect in P. vitulifera but smaller and in P. stylosa. The infructescences of P. stylosa are dense and short while those of P. vitulifera tend to form elongated racemes. Physaria vitu- lifera occurs east of the front range of the Rocky Mountains in Colorado (Mulligan, 1966b). 16 REED C. ROLLINS THLASPI Since the work of P. Holmgren (1971), the features of Thlaspi previously used for taxonomic purposes have been known to be unusually inconstant. In her detailed study of North American representatives of the genus, she found that many of the previously recognized taxa (Payson, 1926) graded into each other almost imperceptably in such a way as to weaken or cancel differences thought to characterize recognizeable taxa. She ended up with four species for all of North America, but included five infraspecific taxa under T. montanum L. Two of the species, T. arcticum Porsild and T. mexicanum Standley, are restricted in their distribution at the limits of the occurrence of Thlaspi in North America, the arctic and subarctic on the one hand and Mexcio on the other. The other species with a restricted range is T. parviflorum A. Nelson, which occurs from north central Wyoming west- ward to central Idaho. Otherwise, T. montanum, including its several vari- eties, is found from west Texas and northern Mexico to Washington and Montana. This species is very abundant in many parts of its range and is a frequently seen member of the Cruciferae. Of concern in the present study is T. montanum var. idahoense (Payson) P. Holmgren, which is confined to central Idaho. The reason is that an underscribed species of Thlaspi has been discovered which is related to var. idahoense, to which the new species must be com . The new taxon is described below, followed by a comparison of these two taxa. V Thalaspi aileeniae Rollins, sp. nov. Herba perennis caespitosa glabra: caudicibus congestis; caulibus simplicibus, rigidis, tenuis (1.5-)2-4(-5) em altis; foliis basalibus densis, erectis, carnosis, linearis vel lineari-oblanceolatis integris, (5-)6-9(-10) mm longi gis, sessilibus, (3-)4-6(-7) mm longis, 1-2 mm is; i escentiis densis, 1-2 cm is; icellis rectis, (2-)3-4(-5) mm longis; siliquis obovatis vel ellipticis, 4-6(-6.5) mm longis, 2.5-4 mm latis; stylis ca. 1 mm longis; loculis 2-5 is; seminibus crassis, exalatis, bruneis, anguste-ovalis, 1.5-2 mm longis, 1-1.2 mm latis; Holotype in the Gray Herbarium. Idaho. Custer Co.: on a stony flat off road to Cape Horn, between Knopp Creek and Valley Creek, ca. 16 miles NW of Stanley, Custer County, Idaho, aisbocrs ese & Kathryn W. Rollins 83287 with Aileen G. Roads. Isotypes Ny and to distribu: - 2-4(-5) cm tall including mature infructescences; basal leaves tufted, erect, 1-1.5 mm wide near apex and narrowing to point of insertion, (5-)6-9(-10) mm long; cauline leaves (0-)1-3(-4) per stem, oblong, sessile, non-auriculate or with small auricles on uppermost leaves, (3-)4-6(-7) mm long, 1-2 mm wide; infructescences dense, 1-2 cm long; pedicels straight, nearly at right CRUCIFERAE OF WESTERN NORTH AMERICA ig acute at base of style, 4-6(-7.5) mm long, 2.5-4 mm wide; styles 1 mm or less long; ovules 2-5 in each locule; seeds plump, brown, wingless, narrowly oval in outline but tapered toward each end, 1.5-2 mm long, 1-1.2 mm wide; cotyledons accumbent. Flowers not known. off Stanley Creek road, 6 5 miles NW of Stanley, July 14, 1983, Reed C. - a WwW. or 83283 with Aileen G. Roads (GH, NY). The most easily seen, and in many ways the most distinctive, features of Thalaspi aileeniae are the basal leaves and growth habit. The narrow, erect basal leaves are like those of no other North American species of Thlaspi. But because there is gradual flaring from the petiolar area to the broadened blade in T. montanum L. var. idahoense (Payson) P. Holmgren, this taxon comes closer in leaf-form to T. aileeniae than any other. Similarities between these two taxa occur also in silique form, and the shortness of the sterile portion of the fertile stems. They differ in style length, density of the infruc- tescence and auriculation of the cauline leaves. Substantial auricles are found on all cauline leaves of var. idahoense but none are present or there are but the barest suggestions of auricles on the uppermost leaves of T. aileeniae. The lower cauline leaves are definitely non-auriculate. In the latter species, the infructescences are so dense and so short that it approaches a subum- bellate condition. In contrast, the infructescences of var. idahoense are defi- nitely elongated. An exceptional collection (Rollins 79384) from 14.6 miles south of Stanley, Idaho, has somewhat shortened infructescences but the cauline leaves are distinctly auriculate, the basal leaves have blades, and the styles are 1.5-2 mm long, all features characteristic of var. idahoense. The styles of T. aileeniae are 1 mm long or less and in this respect are more like those of T. parviflorum and T. mexicanum than any other North American taxon I ‘sn pleased to name Thlaspi aileeniae for my sister, Aileen Gates Roads, who has not only supported my research, but she participated in the field work resulting in the discovery of this previously undescribed species. ACKNOWLEDGMENTS We are indebted to Scott Peterson, Karen Wiley-Eberle, and Dieter Wilken for a populations of f Lesquerella and Physaria ria in Rio Blanco Co unty, Colorado, an o Klaus the summit of St. Mays Pek in the Biterot Range . of southwestern Montana. Dr. Patricia Holmgren has kindly examined our collections of Thlaspi aileeniae and corroborated our con- represented an undescribed species. Financial support was provided by the Roads Grant of the Gray Herbarium. LITERATURE CITED DETLING, L. E. 1939. A revision of the North American species of Descurainia. Amer. Midl. Naturalist 22: 481-520. 18 REED C. ROLLINS HitcHcock, C. L. 1941. A revision of the Drabas of western North America. Univ. Wash. Publ. Biol. 11: 1- 132. 1964. In Hitchcock, Cronquist, Ownbey, and Thompson, Vascular Plants of the Pacific Northwest, Part 2, Salicaceae to Saxifragaceae. end a Press, | Seattle. eae & yp pees ss Hooker, W. J. 1830. Flora Boreali- Americana, Vol. 1, Pt. 1, Pda pp. 37-70. LICHVAR, R. W. 1983. A new sp Vyoming. Brittonia 35: 150- 155. MULLIGAN, G. A. 1966A. Two new species of Physaria (Cruciferae) in Colorado. Canad. J. Bot. 44: gee 1665. 9668. Diploid and autotetraploid Physaria vitulifera (Cruciferae). Canad. J. Bot. 45: 1967. Physaria didymocarpa, P. brassicoides, and P. floribunda (Cruciferae) and their close ponte R. Her- MEXICAN CRUCIFERAE 23 nandez-V. 4606 (CAS, ENCB). — 3 km al NE de Bernal, Rzedowski 25563 (ENCB); same locality, Rzedowshi 26069 (EN Lesquerella roseii mee nom. nov., based on Synthlipsis lepidota Rose,” Contr. U.S. Nat. Herb. 8: 294, 1905, not Lesquerella lepidota Cory, Rhodora 32: 110, 1928. L. argentea (Schauer) S$. Wats., subsp. lepidota (Rose) Rollins & Shaw, The Genus Lesquerella (Cruciferne) in North America, p. 159, Harvard Univ. Press, 1973. The known material of Lesquerella roseii falls into two minor taxa as shown by the following key. KEY TO THE VARIETIES Styles slender, 2-3 mm long; pedicels 7-12 mm long var. roseii. Styles stouter, 1-1.5 mm long; pedicels 3-6 mm long var. perotensis. L. roseii Rollins var. roseii Mexico. Distrito Federal 2 km E de Ixtapa, Rzedowshi 20083 (os DUKE, ENCB, GH). Hidalgo: near Tula, Pringle 6899 (holotype, Us; isotypes B, GH, MO, NY, US); same locality, Rose et al. 8360 (GH, 3 Zimipan (2), pr ob 691 (K, GH); 14 km al E de Ixmiquilpan, Quintero 2913 (ENCB); Zem Ventur. ). Puebla: Atezcaca, Lago Volcanico con cenizas, Boege 183 (cas); Zacatepec, Mn. de Oriental, F. Ventura A. 4068 L. roseii var. perotensis Rollins, var. nov. Herba humifusa; Sarre fructiferis sigmoideis, 3-6 mm longis; siliquis ellipticis vel late gis. Holotype in the Gray H Herbarium. Mexico. Veracruz: de secundaria, arenoso; phere de astige meted 2700 m, sabi 1976, —— Peli n R. et al. 201. OTHER SPECIMENS STUDIED uca, 8815 (GH). Vecuiine al SW de’ J ers de Alchichica, atime H. Ramos 155 (GH); Justo Sheers Mn. de Perote, F. Ventura A. 4010 (cas). Seageevenns ——- seins, i. nov. parce recurvatis, -10 compressis, 7-10 mm ace 3-5 mm bgt ae is: sts 2-3 mm longis; loculis Cae en oe be ems prostrate, radiating; petals clear white (!) pod compressed contrary to septum,” N of Tehoaan, 5650 ft, Nov. 19, 1966, H. D. Ripley & R. C. Barneby 14734. Isotype: NY Perennial with a taproot, densely pubescent, silvery, trichomes radiate, closely appressed, rays simple, ca. 20, fused toward base for ca. ¥ of their lengths; strate, simple, nae Aiea bee Giclee petiolate, oblanceolate, obtuse, shallowly sinuate to few-lobed, 1.5-3(-4) em long, 4-8 mm wide; cauline leaves entire, narrowly oblong, obtuse, cuneate at base, 8-13 mm long, 2-3.5 mm wide; infructescences usually e often occupying half the stem length; fruiting pedicels at ae aes mchic to remowhet vecuives), usually sigmoid, 5-8(-10) mm long; siliques e 24 REED C. ROLLINS widely spreading to ascending, elliptical, compressed contrary to septum, 7- 10 mm long, 3-5 mm wide; valves rounded on back; styles 2-3 mm long: replum narrowly oblong, acute above, 2-3 mm wide; septum usually with a large perforation; ovules 3-7 in each locule; seeds nearly orbicular, wingless, thick but compressed, ca. 2 mm diameter, mucilaginous when wetted: coty- ledons accumbent. Information given by the collectors is quoted above from the herbarium label because this tells us the flowers have white petals. There are no flowers on the two sheets of specimens at hand, so that flower color could not be determined independently. Lesquerella sinuosa is unquestionably related to L. roseii. A fundamental difference is in the ovule number as indicated in the above key, and the habit of the two species is quite different. The stems of Lesquerella sinuosa are prostrate, simple, and radiate from an enlarged crown while those of L. roseii are upright to decumbent at base, usually branched and arise from a small crown. Because the siliques of L. sinuosa are not as strongly compressed as those of L. roseii, the replum is wider and less linear than in the latter species where the siliques are strongly flattened contrary to the septum. There is considerable variation in leaf margin on the basal leaves of L. sinuosa. In one plant on the holotype sheet, the leaves are deeply cut, producing large terminal lobes and a few minor lobes along the lateral margins. Basal leaves on other plants of the type collection are only shallowly sinuate, and a range from one extreme to the other can be seen ROMANSCHULZIA There are several specimens of Romanschulzia in different herbaria that Herba i" : annua vel bi - con ta; tri a ack ae pee Ne . hirsutis, ca. 1 m altis; foliis inferne ignotis; foliis caulinis auriculatis, amplexicauli ulibus, ovatis, lobatis vel integris, sparse hirsutis, usque ad 1.5 dm longis, 5 cm latis, pedicellis fructiferis remotis, divari .* i a is; siliquis sessilibus, rectis, > b 35-4, en i Be is: st in: ’ — et —— ; ne stylo minus 1 mm MEXICAN CRUCIFERAE 25 Robust single-stemmed annual or biennial, erect; trichomes simple, stems leafy, single, branched above, hirsute except above, ca. 1 m tall; lower leaves not known; middle and upper leaves with a strong mid-vein, auriculate, amplexicaul, ovate, lobed to entire, sparsely hirsute but more densely so on the veins, up to 1.5 dm long and 5 cm wide, middle remotely denticulate, upper entire and apiculate; fruiting pedicels remote, divaricately ascending, straight, glabrous, 3-6 mm long; siliques sessile, divaricately ascending, straight, glabrous, terete to slightly compressed contrary to septum, 3.5-4.5 cm long, 1.5-2 mm wide; valves 1-nerved the full length; styles less than 1 mm long; ovules numerous; funiculi expanded toward base; septum with prominent elongated areolae; seeds slightly embedded in septum, in a single row, plump, irregular in shape, usually slightly longer than broad, just over 1 mm long, not mucilaginous when wetted; seed coat grayish, foviate; coty- ledons obliquely incumbent. Romanschulzia correllii (named for the senior collector, the late Donovan S. Correll) is most closely related to R. elata Rollins, a species so far known only from the state of San Luis Potosi. Both of these species are tall, single- stemmed herbs with relatively large amplexicaul leaves. Large leaf-like bracts subtend the branches and both have thick septa in the siliques which tend to partially envelope the seeds, which are also similar in the two species. Plants of the species differ in length and position of the siliques, length and position of the pedicels, presence or absence of a gynophore and presence or absence of trichomes on the stems and leaves. In R. correllii, the divari- cately ascending siliques are 3.5-4.5 cm long; the pedicels are divaricately ascending and only 3-6 mm long; there is no gynophore; and the stems and leaves are hirsute, the latter sparsely so. On the other hand, R. elata has siliques widely spreading to slightly ascending shat: are 2-3 cm long; the up to 1 mm dose aa the plants are entirely oan ‘insofar as they are presently known. The latter qualification has to se made Decne oe lower parts of the plants are not present on the tw R. elata. Romanschulzia correllii is the most northerly species al the genus. Romanschulzia rzedowskii Rollins, sp. nov. Herba el eases —_— ca. 4 dm alta; cauli caulibus inferne — _— obovetis vel oblong, integris, ‘tas vel acti, 47 em longs, 1.53 om lats, a saccatis, late ; at =a 1 mm longis; ninikus ovoideis, exalatis, uniseriatis, ca. 1.2 mm longis, ca. 1 1 mm latis; bentibus. Holotype i the G Herbarium. Mexico. Jalisco: Veriente N Se Arroyo de Aguas, Municipio ici dc Tienes TL VEEIOT®, ah. 2100 t, J Rzedowski 27: 26 REED C. ROLLINS Annual or biennial, erect, ca. 4 dm tall; stems one or two, branched above, pubescent with minute simple trichomes below, becoming glabrate upwards, branches arising in axils of leaves, basal leaves not present; cauline leaves monomorphic, auriculate, broadly obovate to broadly oblong, entire but with remote minute teeth, midvein prominent, obtuse to acute, 4-7 cm long, 1.5- 3 cm wide, those of upper branches smaller, lower sparsely pubescent with minute simple trichomes, upper glabrate; inflorescences lax, flowers remote; sepals glabrous, nonsaccate, broadly oblong to nearly elliptical, quickly deciduous, ca. 2.5 mm long, ca. 1.5 mm wide; petals none; stamens nearly equal; filaments abruptly dilated at base, purplish, ca. 1.5 mm long; anthers less than 1 mm long, fruiting pedicels arched downward, glabrous, 4-6 mm long; siliques terete, sessile, straight, glabrous, pendent, 2.5-3 cm long; valves with a strong nerve from base to apex, net-veined; styles ca. 1 mm long; stigmas capitate, shallowly lobed; lobes over replum; seeds plump, slightly longer than broad, wingless, tan, uniseriate, ca. 1.2 mm long, ca. 1 mm wide, embedded in tissue of septum; seed-coat with a reticulate pattern; funicle flattened; cotyledons incumbent, smaller than radicle. It is hard to pinpoint the nearest relative of Romanschulzia rzedowskii because of its recurved pedicels and pendent siliques. In these respects, it is like but one other species, R. apetala Rollins. There are substantial dif- ferences in pedicel and silique position in the other species of Romanschul- zia, where the range goes from — srending to erect, but not moar kedlby reflexed. Romanschulzia apetala Ro close relative of R. rzedowskii oo of its broad flattened siliques and ge elongated PERE Most species of Romanschulzia have nar- ecimeters long which are composed of numerous aioe arranged small oa A more lax type of inflorescence character- istic of R. rzedowskii is found in R. schistacea Rollins, a species so far known only from Hidalgo. The fact that R. rzedowskii is apetalous is an interesting feature that is matched by R. subclavata and R. apetala. It is a pleasure to name this species in honor of the collector, Dr. Jerzy ki, Professor and veteran botanist of Escuela Nacional de Ciencias Biolégicas, Instituto Politécnico Nacional, México. THELYPODIOPSIS In my recent treatment of Thelypodiopsis (Rollins, 1982), I overlooked a misidentified specimen that represents an undescribed species. Because of its superficial resemblance to Dryopetalon runcinatum var. <-cegeon Daan specimen had been placed there. But the petals are entire and other features phen ese eas de icone coe rilacic > iol A ARS superne glabris, se ad bias at os Ges cs integris vel MEXICAN CRUCIFERAE 27 lobatis, sparse pubescentibus, usque 1 dm longis, superne lobatis, glabris; inflorescentiis laxis; sepalis oblongis nonsaccatis, glabris, 3-3.2 mm longis, + ae 5 mm latis; petalis albis, — vel late oblongis, 5-6.5 mm longis, ca. 2.5 mm latis; iferis tenuis, rectis, late divaricatis, (7- )9-11(-13) mm longis; ee late divaricats, — glabris, stipitatis, 2. 3cem sie plus manieve ? mm tis; ‘ tipo ca bilobatibu: , ca. 1mm longs pt Sess Holohpe in the Gray soe eae Mexico. Sinaloa: on a steep pene tos. slope, growing with Bursera, Ipomoea arborescens and Ficus; Cation de Tarahumare een Arroyo Verde and Rancho per gcsi Sierra Surutato, elev. 3,200 ft., Mncpo. ay 27 Feb. 1968, D. E. Breedlove 15913. Isotype: CAS Annual or ee shesccnce of simple acerose trichomes; stems erect, one or few, branched, hirsute below, glabrous above, up to 5 dm tall; leaves monomorphic, petiolate, thin, prominently veined, lower elliptical to broad- ly obovate, obtuse, sparsely pubescent, entire to few-lobed, up to 1.5 dm long including petiole, 3-5 cm wide, margins sinuate to nearly entire, middle leaves deeply lobed, glabrous or nearly so, upper leaves linear-lanceolate, glabrous, short-petioled, sparsely dentate to somewhat lobed; inflorescences lax; flowering pedicels very slender, spreading nearly at right angles to rachis to slightly ascending, remote; sepals oblong, greenish with a distinctive white margin, thin, transparent, nonsaccate, glabrous, 3-3.2 mm long, 1.2-1.5 mm wide; petals white, obovate to broadly oblong, 5-6.5 mm long, ca. 2.5 mm wide; filaments slender, nearly equal, ca. 3 mm long; anthers oblong, ca. 1 mm long; fruiting pedicels slender, straight, glabrous, at right angles to rachis to slightly ascending, (7-)9-11(-13) mm long; siliques widely spreading to somewhat ascending, terete, glabrous, stipitate, 2-3 cm long, less than 1 mm in diameter; stipe 1.5-2 mm long; stigma bilobed with lobes over replum; seeds oblong, wingless, ca. 1 mm long, less than 1 mm wide; cotyledons incumbent. > OTHER SPECIMENS STUDIED. Mexico. Sinaloa: Sierra Suratato, Cafion de Tarahumares, below the settlement of Tarahumares, Mncpo. Sinaloa y Vela, 3,000 ft., 4 March 1971, D. E. Breedlove 19108 (cas). ACKNOWLEDGMENTS 1 am much indebted to Dr. Hermilo J. Quero R., oe aeeke pee de Biologia, U E pport our field work in Hi . 2. 2s bee Dp. Cal Pa eae eg and much needed help during our stay in Mexico City. ~s agmagsaoute tele hook Mario Sousa P. who provided transport, guidance, and linguistic help that made our work effective and worthwhile. LITERATURE CITED RO.ins, R. C. 1941. Some generic relatives of Capsella. Contrib. Dudley _ 3: 185-189. Contrib. Dually Herb. 3: 199-207. ae agate pa 7. ontrib. Sahay Herb. 3: 217- —— Some primitiv Mexican Cruciferae. 58: 1 SF ete cai tants. Cooy Hexb. 2087 1-102. ——_—_AND E. A. SHAW. try. The Com Lenawee (Cruciferae) in North America. 1-288. Harvard Univ. Press, Cambridge, Mass.