"•I-'NO/S LIBRARY useasr^ JUL 2 4 1984 Tht Library of the FIELDIANA MAY271975 DO 19 D V um.ulSIl) 01 ,!,!,,„. •t Urbani-CrMmpaigr. Published by Field Museum of Natural History Volume 36, No. 9 December 9, 1974 Studies In American Plants, VI DOROTHY L. NASH SUPERVISOR. HERBARIA FIELD MUSEUM OF NATURAL HISTORY COMPOSITAE Recent studies in the Compositae for the "Flora of Guatemala" have resulted in the discovery of two new species and led to the following new combinations in the family. ASTEREAE Archibaccharis aequivenia (Blake) D. Nash, comb. nov. A. standleyi Blake var. aequivenia Blake, Brittonia 2: 340. 1937. Since Blake described the var. aequivenia, additional collections indicate that this is a fully distinct species, consistently different from A. standleyi. The staminate heads of the Honduran A. stand- leyi have only 7-15 hermaphrodite flowers; those of the Guatemalan A. aequivenia have 22-25. The leaves of A. standleyi are 2-5.5 cm. long and rounded at the base; those of A. aequivenia are 4-16 cm. long, attenuate to a cuneate base. INULEAE Gnaphalium alatocaule D. Nash, sp. nov. Herbae erectae, ramosissimae in inflorescentiis; folia alterna, sessilia, linearia, 2-8 cm. longa, 0.2-0.4 cm. lata, acuminata, Integra, eglandulata, basi amplexicauli, longe decurrente alata ultra proximum nodum percurrente, superficie superna glabrata vel tenuiter tomentosa, inferna dense tomentosa; squamae albidae, nitidae, ovatae, lan- ceolatae vel lineares, obtusae; flores hermaphroditae 7-10, femina 50-60; pappi setae seperatim deciduae. Erect, coarse herbs, probably at least 1 m. tall, usually much branched in the area of inflorescence, the stems terete, more or less arachnoid-tomentose; leaves alternate, sessile, linear, acuminate, mostly 2-8 cm. long, 0.2-0.4 cm. wide, the base amplexicaul and long-decurrent on the stem, forming a conspicuous wing reaching beyond the next node, the margins often revolute, the upper surfaces green, glabrate or thinly US ISSN 0015-0746 Library of Congress Catalog Card Number: 68-26374 Publication 1198 73 74 FIELDIANA: BOTANY, VOLUME 36 tomentose, eglandular, the lower surfaces densely covered with white, feltlike, arachnoid tomentum; inflorescences broad and open, composed of numerous, small, rounded cymose glomerules of sessile heads at the ends of the stems and branches; in- volucres campanulate, about 4 mm. long, 4-5-seriate, the phyllaries glabrous, shining, white or cream-colored, the outer ones ovate, acute, the middle ones lanceolate, obtuse and often somewhat erose, the innermost ones linear, obtuse or subacute and often erose; heads each with 50-60 filiform, pistillate flowers and 7-10 tubular her- maphrodite flowers; achenes brown, glabrous, about 0.5 mm. long; pappus white, the bristles falling separately from the achenes. Guatemala: Casillas, Dept. Santa Rosa, 4,000 pp., Jan. 1893, Heyde et Lux 4217 (type, F; US); sin. loc., Heyde 583 (US). The holotype sheet with the original label reads, "Casillas, . . . alt. 4,000 pp.", but the isotype, U.S. National Herbarium sheet No. 1403098, with the same collection number and date, has a printed label reading, "Carrizal, . . . alt. 5,000 pp." This species is similar in general appearance to the South Ameri- can G. gaudichaudianum DC., in which the upper leaf surfaces are glandular, the leaf bases are only briefly decurrent on the stem or reach only about half way to the next node, and which has more than 100 flowers per head. Gnaphalium liebmannii var. monticola(McVaugh) D. Nash, comb. nov. G. vulcanicum I. M. Johnston var. monticola McVaugh, Contr. Univ. Mich. Herb. 9: 466. 1972. VERNONIEAE Vernonia tenella D. Nash, sp. nov. Frutices erecti ad 3 m. alti vel interdum aliquot scandentes; folia alterna., petiolis brevibus, laminae 5-11 cm. longae, anguste lanceolatae, oblongo-lanceolatae vel ellip- ticae, acuminatae, basi attenuatae, decurrentes in petiolis, integrae, quasi glabratae; cymae ramis scorpioideis, 5-10 cm. longae, graciles, usque ad 0.5 mm. diametro, min- ute tomentosae; capitula sessilia, secunda, remota; squamae imbricatae, interiores lineari-oblongae, subtriangulares vel obtusatae; flores circa 15, corolla lavandulacea vel purpurea; achenia 1.5-2 mm. longa, pilosa; pappus fulvus, setae plus minusve 6 mm. longae. Erect shrubs to 3 m. tall or sometimes sprawling or somewhat scandent, the stems terete, striate, puberulent or thinly appressed-pubescent to glabrate; leaves alternate, on petioles 0.5-1.5 cm. long, the blades narrowly lanceolate to lance-oblong or elliptic, 5-11 cm. long, 1.5-3 cm. broad, acuminate, attenuate to the base and decurrent on the petiole, essentially glabrous above or puberulent along the costae, glabrous beneath or with some pubescence usually confined to the costae and veins, the margins entire; inflorescences composed of branching scorpioid cymes, the branches very slender, mostly 5-10 cm. long, about 0.5 mm. in diameter, minutely tomentose; heads sessile, secund, remote; involucres campanulate, 6-8 mm. high, more or less tomentose, the phyllaries imbricate, the outer and middle ones acute, the inner, longer ones linear- NASH: AMERICAN PLANTS. VI 75 oblong, subacute or subtriangular to obtuse; flowers about 15 to each head; corollas lavender or purple; achenes 1.5-2 mm. long, pilose; pappus pale fulvous, the outer scales short, to about 1 mm. long, irregular, the bristles about 6 mm. long. Guatemala: Montane cloud forest area, outer slopes of Ta- jumulco Volcano, Sierra Madre Mountains, 8-10 km. west of San Marcos,Dept. of San Marcos, alt. about 2,300 m., L. O. Williams et al. 26876 (type, F); wet mountain forest near Aldea Fraternidad, west facing slope of the Sierra Madre Mountains, Dept. of San Marcos, alt. 1,800-2,400 m., Williams, Molina, and Williams 26094 (F) and 26264 (F, US). Similar in appearance to V. polypleura Blake, which differs in its densely pilose lower leaf surfaces, its larger cymes, 15-30 cm. long, its heads with 17-25 flowers each, and in its shorter pappus bristles, 4-5 mm. long. UNIVERSITY OF ILIINOIS-URBANA