114 PROCEEDINGS OF THE AMERICAN ACADEMY. 



Chrysanthellum mexicanum. Annnal : stem simple or much- 

 branched, erect or ascending, 1 to 3 dm. high, glabrous or sparingly 

 hirtellous, apj^arently somewhat glaucous, often purplish at the base: 

 leaves petiolate, tripinnatcly parted, glabrous on both surfaces, promi- 

 nently veined ; divisions narrow, ajjiculate-acute : inflorescence a subco- 

 rymbose cyme : heads small, 3 to 4 mm. high : involucre subcampanulate, 

 glabrous ; scales of the involucre ovate-oblong, acute : outer achenes 

 subterete, the inner strongly ob-compressed, narrowly cartilaginous- 

 margined and conspicuously ciliate. — Mexico. State of Jalisco : 

 banks of ravines near Guadalajara, 10 September, 1890, C. G. Pringle, 

 no. 8259 (hb. Gr.), distributed as " Chrysanthellum procumbens, Rich."; 

 Tequila, August, 188G, Dr. Edward Palmer^ no. 3G4 (hb. Gr.). State 

 of Chiapas: tableland about Ocuilapa, altitude 1000 to 1200 m., 21 

 August, 1895, K. W. Ndson, no. oOfiS (hb. Gr., and hb. U. S. Nat. 

 ]\Ius.). State of Vera Cruz : Orizaba, Botteri, without number (hb. 

 Gr.). State of San Luis Potosi, altitude 2000 to 2450 m., C. C. Parry 

 ^ Dr. Edward Palmer, without number, coll. of 1878 (hb. Gr.). 



The Mexican and Central American representatives of this genus 

 hitherto have been referred to C. procumhens, Rich., which species, as far 

 as the material at hand shows, is confined to the West Indies, Venezuela 

 and Guatemala. C. mexicanum is readily distinguished from C. pro- 

 cumhens by its more erect, stricter habit, and by the uniformly tripiu- 

 natisect leaves. In habit and in foliar characters C. mexicanum bears a 

 close resemblance to C. Indicum, DC. from wdaich it differs in having 

 smaller, narrowly cartilaginous-margined and conspicuously cil'ated 

 achenes. 



Bidens bicolor. Stem stramineous, striate, hirsute-joubescent to 

 essentially glabrous, rather freely branched above: leaves pinnately 3-5- 

 parted ; divisions ovate to ovate-lanceolate, 1.5 to 5 cm. long, 0.5 to 



2 cm. broad, acute to acuminate-acute, dentate, sparingly pubescent to 

 quite glabrous, paler beneath : inflorescence a loose subcorymbose cyme : 

 heads, including the rays, 2.5 to 6 cm. in diameter: involucre biseriate, 

 more or less hirsute ; outer involucral scales linear-oblong, subfoliaceous, 

 usually spreading : ray -flowers 5 or G, neutral ; rays oblong, 1.5 to nearly 



3 cm. long, dark-nerved in the earlier stages, conspicuously purple- 

 maculate at the base: disk-flowers numerous: pappus retrorsely few- 

 barbed : mature achenes not seen. — Mexico. State of Oaxaca : altitude 

 1750 m., July-August, 1900, C. Conzatti Sf V. Gonzalez, nos. 1008, 

 1009 (hb. Gr.). Apparently most nearly related to Bidens grandijlora, 

 Balb. 



