8(6). Plant erect, to 9 dm. tall, typically smooth and glabrous; leaves in whorls 

 of 4; flowers bright-white 8. G. boreale. 



8. Plant weak and reclining; leaves in whorls of 6 to 8, more or less scabrid or 



hispid; flowers dull-white or greenish-white (9) 



9(8). Leaves mostly oblanceolate, the margins retrorsely bristly; stems retrorsely 

 bristly on the angles, usually pubescent above the nodes; annual 

 9. G. Aparine. 



9. Leaves mostly elliptic-lanceolate, the margins with ascending cilia; stems 



smooth; perennial, stoloniferous 10. G. triflorum. 



1. Galium microphyllum Gray. 



Diffusely spreading or ascending perennial, smooth and glabrous but not shin- 

 ing; branches to 3 dm. long; leaves firm, shorter than the internodes and narrowly 

 linear, usually mucronate, with narrow midrib prominent beneath and callous 

 naked margins, to 12 mm. long, usually smaller; flowers solitary on a very short 

 or on a longer and pedunclelike axillary branchlet and sessile in its whorl of in- 

 volucriform leaves, or this proliferous and bearing a second whorl and flower; 

 ovary and young fruit scabro-puberulous or at length granulose, at maturity fleshy- 

 baccate. Relbunium microphyllum (Gray) Hemsl. 



In canyons and rocky ravines and on ledges and talus slopes, mostly along 

 streams, edge of wet meadows, moist woods, cracks in boulders, in mts. of the 

 Tex. Trans-Pecos, N. M. (rather widespread) and Ariz. (Greenlee to Coconino 

 and Mohave, s. to Cochise. Santa Cruz and Pima cos.), May-Oct.; from Tex. to 

 Ariz, and adj. Mex. 



2. Galium Brandegei Gray. 



Plant glabrous throughout, low and simple to matted and freely forking, the 

 weakly ascending stems 5-15 cm. tall; leaves of primary axes in whorls of 4, 

 oblanceolate to oblong-spatulate, fleshy-thickened, obtuse at apex, 4-10 mm. long; 

 flowers solitary or sometimes 2 or 3, on simple or forking peduncles, these and 

 the straight to arching pedicels 3-10 mm. long; pedicels becoming stout in fruit; 

 fruits smooth, 1.5-2 mm. in diameter. G. trifidum var. pusillum Gray. 



At edge of water of small ponds, along streams and in low wettish grounds, 

 in N.M. (Taos and San Miguel cos.) and Ariz. (Coconino Co.), May-Aug.; 

 Greenl. and Lab. to Alas., s. to N. M., Ariz, and Calif. 



3. Galium obtusum Bigel. Bluntleaf bedstraw. 



Stems erect, from capillary rhizomes, simply (not intricately) branched, to 

 about 8 dm. high, smooth, stiffish; leaves mostly in fours, rarely in fives or sixes, 

 elliptic-oblong to lanceolate or broadly linear, obtuse, those of the primary axis 

 to 3 cm. long and 6 mm. broad, loosely spreading, slightly scabrous on the 

 margins; cymes terminating stems and branches, their several flowers grouped 

 in twos or threes; the straight peduncles and pedicels ascending in anthesis, often 

 divergent in fruit; corolla white, 2-3 mm. broad, commonly with 4 acute lobes; 

 fruits globose, smooth, 2.5-3.5 mm. in diameter. G. trifidum var. latifolium Torr. 



In low woods, bogs at edge of ponds, swamps and wet shores in Okla. {Water- 

 fall) and e. Tex., Mar.-July; from Fla. to (?)Ariz., n. to s.w. N.S., s. and w. N.E., 

 s. Ont., Mich., Wise, Minn, and Neb. 



4. Galium trifidum L. Fig. 722. 



Weakly erect perennial from a slender rootstock, often freely branching to 

 form dense mats, to about 3 dm. high, smooth and glabrous except for the 

 retrorsely scabrous angles of the stems and usually more hispidulous and sparse 

 roughness of the midrib beneath and margins of the thin leaves; leaves mostly in 



1540 



