Notes on Southwestern and Mexican Plants
BRIEFER ARTICLES 2I9 or expanded, even deflexed and almost involute at times, and wavy or lobed ; entirely white when young, shading in age into ochraceousbuff, ochraceous, and even orange above, remaining more pallid below; hygrophanous when moist, and slightly viscid or glutinous; flesh very soft, almost of waxy consistency, composed of very loosely woven mycelium in the center, becoming denser at the surface. Stem solid, equal or slightly broadened upward, 0.5-i ..... in 'diameter, white
... diameter, white pruinose becoming pubescent with scattered white hairs at base. The hymenium surrounds the upper two-fifths to one-half of the length of the fruit body; basidia clavate, I8-24X 4, 4-spored, sterigmata up to 4/. in length; spores broadly elliptical to subglobose, smooth, white, 3-4,1; cystidia white, numerous, often 6o-7oX4-61k, usually curved and irregularly swollen toward the base where they arise from the trauma, extending beyond the basidia only when young and by 2-41, thin-walled and containing substances which blacken with osmic acid. Type in Cornell University Herbarium, no. I5,445, collected from very rotten twigs and leaves of deciduous trees and conifers, but only under prostrate branches of laxus canadensis, in Fall Creekl gorge, Ithaca, N. Y., between October i9 and November i9, I903.-Small, Fl. Southeastern U. S. I308. I903.-C. NVta//ii Spreng Syst. 4: (Suppl.) 298. i827. -CC mexicana DC. Prodr. 6: 575. i837. -PletoeephaUus americanus Don in Sweet's Brit. Fl. Gard. 2: pI. 51. i831 ; Spach, Hist. Veg. IO: 63. UNITED STATES. Arkansas: specimen ex hb. JDuravd. Louisiana: Dr. Leavenwort/. Texas: Pope, Lindheimer, nos. I I4, 34; dry prairies, near Dallas, Hall, no. 373, Reverchon; Drummond, no. i69; between Bexar and the Trinity River, Ber/andier, nos. 430, 1750; Kerrville, altitude 490 to 6I5 , Heller, no. I774; Weatherford, Tracy, no. 7896. New Mexico: Jornado del Muesto, Dr. IWislizenus; exp. from western Texas to El Paso, Wright, no. 405; White Mountains, altitude i850m, Woo/on, no. I95. MEXICO. Coahuila: Saltillo, Dr. Edward Palmer, nos. 766 (coll. of I880), 294 (coll. of i898) whiteflowered form. Chihuahua: Bachimbo Canion, Pringle; Rio Sta Maria, Thurber, no. 748. This content downloaded from 141.218.001.105 on August 12, 2016 11:52:14 AM All use subject to University of Chicago Press Terms and Conditions (http://www.journals.uchicago.edu/t-and-I 904] BRIEFER ARTICLES 2 2 1 ** Involucral bracts greenish or stramineous below, conspicuously tipped with chestnut-brown, pectinate-fimbriate with 8-12 pairs of lateral rather slender teeth. C. Rothrockii Greenman, n. sp. Annual or biennial (?), 3-Iod high: stem erect, simple below, sparingly branched above, sulcatestriate, glabrous or slightly hirtellous; leaves lanceolate to oblonglanceolate, 3--12C' long, 1-3.5cm broad, sessile and often semiamplexicaul, acuminate, acute, sometimes terminated by a conspicuous mucro, entire to slightly sinuate-dentate, h-irtellous-puberulent on both surfaces, hispidulous on the margins, resiniferous-dotted; the uppermost leaves much reduced and not infrequently subfimbriate near the tip: peduncles thickened above: heads large, 3-5 cn high, including the rays 3-I5Cm in diameter: involucre subcampanulate, in well-developed specimens about 3 Cla high and 4 cm broad; bracts of the involucre about 9-seriate, rather closely imbricated, lanceolate, pectinate-filbriate in the upper third, bearing 8-12 pairs of brownish ciliated rather slender teeth : the neutral marginal flowers (rays) elongated, conspicuous, usually purple, much exceeding the lemon-yellow flowers of the disk: mature achenes oblong-obovate, 5mtn long, black and simooth.-C. americana Rothrock in Wheeler's Report i8o. i878, not Nutt.-Centaurea sp. Engelm. in Wislizenus Report 107. i848, Reprint 23. UNITED STATES.