PROCEEDINGS OP THE AMERICAN ACADEMY. 



cuneate base, thickish, glabrous and covered on both surfaces (under a 

 lens) with very numerous dark glandular dots; blade 8 to 10 cm. long, 

 2.3 i" '■'< cm. broad, pinnate-veined, the midnerve prominent beneath, 

 grooved above; petiole 1.8 cm. long; the upper axils proliferous: in- 

 florescence relatively small, 1 cm. broad, a trichotomous Bhort-peduncled 

 corymb; involucral bracts •"> to 6 mm. long, viscid-pubescent upon the 

 back, acutish : flowers 5; corolla, apparently white, about twice the 

 length of the involucre, the tube viscid-puberulent : achen< - Bmooth or 

 nearly so, crowned with Beveral narrow acute or Bubulate Bcales ; more 

 elongated awns apparently lacking. — Collected by C. & E. Seler in 

 mountain woods between St. Carlo- and St. Bartolo, Yantepec, Oaxaca, 

 Mexico, 6 January, 1896, no. 1695. Well marked. Types in herb. 

 Gray and herb. Royal Botanical Museum, Berlin. 



S. s errata, Cav., var. arguta. Leaves narrowly linear, ascending 

 or appressed, sharply serrate with incurved teeth: Bcales of the involucre 

 attenuate to a dark subulate tip. — Collected by C. G. Pringle on the 

 ( i rro Ventoso above Pachuca, altitude 2,900 m., 18 August, 1898, no. 

 7652. 



S. tephra. Ashy throughout with a close pulverulent pubescence 

 not glandular: stems herbaceous, terete, purplish: leaves scattered, 

 elliptical, obtuse, crenate-serrate, '■'> cm. long, half as broad, 8-nerved, 

 finely pubescent upon both surfaces, Blightly paler beneath, mostly eon- 

 duplicate along the midrib, gradually narrowed to a petiole 1 1 cm. in 

 length) : fascicles of smaller leaves on short or scarcely developed axil- 

 lary shoots: inflorescence a moderately dense compound corymb; its 

 branches chiefly alternate, ascending, the lower and longer about s cm. 

 in length, the head- densely clustered at their summits ; individual pedi- 

 cels 1 to 2 mm. long; involucral scales merely acutish, cinereous- 

 puberulent, without evident glands, green or purplish-tinged, 1 to 5 mm. 

 long: flowers 5, about twice the length of the involucre: corolla-tube 

 purplish, puberulent; limb white or nearly bo: achenes black, lucid. 

 •1 mm. lone;, minutely roughened upon the angles; pappus of three awns 

 (equalling the corolla) and •'! short blunt intermediate Bcales. — Col- 

 lected by C. G. Pringle, Siena de Pachuca, Hidalgo, altitude 2,925 m., 

 13 September, 1899, no. 8229. 



Piptothrix Goldmanii. Glabrous: stems terete. Btriate, purple. 

 Blightly lucid: internodes 6 to - s cm. long: branches opposite: leaves 

 deltoid-ovate, acuminate, serrate, .".-nerved from the shortly cuneate base, 

 green and glabrous upon both surfaces, 8 to 10 cm. long, 6 to 8 cm. 

 broad, thin but firm in texture, reticulated veins Blightly prominent upon 



