GREENMAN. — GENUS RELBUNIUM. 469 



* * * Leaves lanceolate to lance-oblong-, pubescent or at least ciliated ; margins 



not conspicuously thickened. 



4. R. hirsutum, Schumann. Low prostrate many-stemmed herba- 

 ceous perennial ; stems 4-angled, covered upon the somewhat thickened 

 ano-les by a spreading hirsute pubescence: leaves lance-oblong, a centi- 

 meter or less in length, 2.5 to 3 mm. broad, hirsute-pubescent upon the 

 upper surface and upon the midrib beneath, ciliate : the 1-flowered in- 

 volucres solitary iu the axils ; their peduncles about equalling the 

 leaves. — Fl. Bras. vi. pt. 6, 116. Galium hirsutum, Ruiz & Pavon, FI. 

 Peruv. i. 59. 



The above description has been drawn from South American material, 

 which well accords with the original characterization of the species by 

 Ruiz and Pavon. No Mexican specimens have been seen by the writer. 

 To this species, however, Martens and Galeotti in Bull. Acad. Brux. xi. 

 pt. 1, 126, doubtfully refer Galeotti's no. 2650, collected on rocks near 

 Mirador, Vera Cruz. 



5. R. ciliatum, Hemsl. Low herbaceous plants : stems obtusely 

 4-angled, glabrous, leaves narrowly lanceolate, 1 cm. or less in length, 

 acute, glabrous upon either surface, margin ciliate : peduncles axillary, 

 solitary, slender, 3 to 5 mm. long ; bracts of the involucre somewhat un- 

 equal, narrowly lanceolate, acute, ciliate : flowers sessile : fruit glabrous. 

 — Biol. Cent. -Am. Bot. ii. 62. Galium ciliatum, Ruiz & Pav, Fl. 

 Peruv. i. 59. G. involucratum, HBK. Nov. Gen. & Spec. iii. 335. 

 Rubia ciliata, DC. iv. 591. — South Mexico in woods of El Sabino near 

 the city of Mexico, Galeotti, no. 2596, ace. to Martens & Galeotti, Bull. 

 Acad. Brux. xi. pt. 1, 126. 



The typical plant is a native of Western South America. No Mexican 



or Central American specimens belonging to this species have been seen 



by the writer. 



* * * * Leaves lance-lingar to linear, more rigid; margins conspicuously 



tliickened. 



6. R. microphyllum, Hemsl. Glabrous throughout : stems rising 

 from a perennial base, erect or nearly so, 1 to 3 dm. high, much branched 

 above ; branches obtusely 4-angled, faces somewhat furrowed : leaves 

 5 to 15 mm. long, usually pungent-tipped ; margins revolute, thickened, 

 smooth: peduncles axillary, solitary : bracts of the involucre similar to 

 the leaves but smaller : flowers sessile ; corolla-lobes ovate, obtusish : 

 fruit glabrous or rarely slightly granulose, sessile or short-pedicellate. — 

 Biol. Cent. -Am. Bot. ii. 63. Galium microphyllum, Gray, PI. Wright. 

 i. 80 & Syn. Fl. N. A. i. pt. 2, 41. — New Mexico, Wright, nos. 234, 



