850 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



8. Leaf blades acute or acuminate and sharply cuspidate at apex, the 



midrib very prominent beneath; plants usually distinctly woody 



above ground; bark of the older stems pale, exfoliating (9). 



9. Plant very rough to the touch, hispid or hispidulous, usually 



suffruticose; leaf blades lanceolate or ovate-lanceolate, thick, 



rigid, the lateral veins obsolete 8. G. stellatum. 



9. Plants scarcely rough to the touch, glabrous or obscurely hispidulous 



(rarely hispid) , suffrutescent; leaf blades thin or only moderately 



thick, scarcely rigid (10). 



10. Leaf blades lanceolate or lance-ovate, 6 to 15 mm. long, 4 to 



7 mm. wide, the lateral veins (1 or more) usually perceptible 



but often very short 9. G. watsoni. 



10. Leaf blades linear, 10 to 25 mm. long, 2 to 3 mm. wide, the 



lateral veins obsolete 10. G. coloradoense. 



5. Hairs of the fruit curved or uncinate; stems entirely herbaceous above 

 ground (11). 

 11. Leaves apparently 5 or more in the whorl; stems long, weak, commonly 

 reclining (12). 

 12. Plant annual, without a rootstock; stems rough to the touch, 

 retrorsely hispid with pricklelike hairs; leaf blades linear, lanceo- 

 late, or oblanceolate; fruit mostly 3 to 4 mm. in transverse diameter 

 at maturity, the hairs stiff, triangular-tuberculate at base, 

 shorter than the transverse diameter of the carpel. 



11. G. APARINE. 



12. Plant perennial, with slender, elongate, branched rootstocks; stems 



not or very slightly rough to the touch, hispidulous, pilose, or 

 nearly glabrous; leaf blades elliptic-lanceolate, broadly oblanceo- 

 late, or oblong-ovate, conspicuously setose-cuspidate; fruit less 

 than 3 mm. in transverse diameter at maturity, the hairs not 

 stiff, scarcely enlarged at base, about as long as the transverse 



diameter of the carpel 12. G. triflorum. 



11. Leaves apparently not more than 4 in the whorl (13). 



13. Flowers in elongate, many-flowered, often rather dense, not very 



leafy terminal panicles; corolla bright white; plant perennial, 

 puberulent or glabrate; stems erect; leaf blades linear to broadly 

 lanceolate, distinctly 3-nerved; fruit often glabrate in age. 



13. G. BOREALE. 



13. Flowers in axillary or terminal, few-flowered, leafy cymes or, if more 



numerous and aggregated in terminal panicles, these very loose 



and very leafy; corolla yellowish or brownish; fruit permanently 



pubescent (14). 



14. Plant annual, hispidulous or glabrate; leaf blades 1-nerved, seldom 



more than 1 cm. long; pedicels curved, usually shorter than the 



fruit 14. G. PROLIFERUM. 



14. Plant perennial, puberulent, soft-pilose, or villous; leaf blades 

 usually indistinctly several-veined, the larger ones commonly 

 more than 1 cm. long; pedicels straight, usually much longer 

 than the fruit 15. G. pilosum. 



1. Galium microphyllum A. Gray, PL Wright. 1: 80. 1852. 



Relbunium microphyllum Hemsl., Biol. Cent. Amer. Bot. 2: 

 63. 1881. 



Coconino County to Greenlee County, south to Cochise, Santa 

 Cruz, and Pima Counties, 1,500 to 7,000 feet, mostly along streams, 

 common, April to October. Western Texas to Arizona and Mexico. 



Several leading authorities recognize Relbunium as a genus distinct 

 from Galium. 



2. Galium asperrimum A. Gray, Amer. Acad. Arts and Sci. Mem. 



ser. 2, 4: 60. 1849. 

 Greenlee, Graham, Gila, Cochise, Santa Cruz, and Pima Counties, 

 4,000 to 9,500 feet, common in coniferous forests in rich soil, July to 

 September. New Mexico, Arizona, and Mexico. 



