Jan., 1915,] The Roses of Ohio. 421 



18. Leaves pinnate with smaller leaf segments between the larger ones; 

 calyx with hooked prickles; flowers with petals in narrow racemes. 

 Agrimonia (18). 



18. Leaves pinnate without the smaller leaf segments; calyx without 



prickles; flowers without petals in heads or spikes. 19. 



19. Leaves ^-23^ in. long; stamens 4; inflorescence a spike. Sangtiisorba .{\Q) 

 19. Leaves YirY2 in. long; stamens numerous; inflorescence a head. 



Poterium. (20). 



1. Geum. Avens. 



Perennial herbs with pinnate or pinnatified leaves with stipules ; 

 flowers solitary or cymose — corymbose; perianth segments 5 

 each; stamens numerous; achenes numerous on a dry receptacle, 

 the persistent styles being straight or jointed, naked or plumose; 

 seed erect, testa membranous. 



1. Flowers purple; calyx lobes erect or spreading; style plumose below. 

 G. rivale. (1). 



1. Flowers white or yellow; calyx lobes strongly reflexed in fruit; style 



not plumose. 2. 



2. Calyx without bracts; flowers less than }/i in. broad, yellow; head of 



fruit long stalked. G. vernum. (6). 



2. Calyx bracteolate; flowers 34~% in. broad. .3. 



3. Petals white. 4. 



3. Petals yellow or cream yellow. 5. 



4. Plants glabrate or softly pubescent; receptacle bristly. G. canadense. (2). 



4. Plants rough-pubescent; receptacle glabrous or downy. G. virginia7ittm.{4:) 



5. Stems bristly-hairy, 13^-3 ft. tall; petals cream-yellow, small, rarely 



exceeding the sepals. G. flavum. (3). 

 5. Stems pubescent, 2-5 ft. tall; petals yellow, large, much exceeding the 

 sepals. G. strictum. (5). 



1. Geum rivale L. Purple Avens. Erect herbs, l'^-2}4 ft. 

 high; basal leaves pinnate, the side leaflets being much smaller 

 than the tenninal leaflets, irregularly lobed and dentate; stem 

 leaves simple or 3-parted; flowers purple, styles becoming plumose 

 in the fruit. Geauga, Champaign. 



2. Geum canadense Jacq. White Avens. Erect, softly 

 pubescent or glabrate herbs, branched at the top, l^^-S ft. high; 

 leaves 3-parted, ovate or obovate, velvety pubescent or glabrate 

 beneath; flowers, white. General. 



3. Geum flavum (Port.) Bickn. Cream-colored Avens. 

 Stems erect, l>^-3 ft. tall, bristly-hairy below; stipules large, 

 foliaceous; leaves usually pinnate, those above sometimes entire; 

 flowers cream-yellow; head of fruit sessile. No specimens. 



4. Geum virginianum L. Rough Avens. Stems with bristly 

 hairs ll4-2 ft. high; petals creamy-white, rather inconspicuous, 

 being exceeded by the sepals; receptacle glabrous or down^^ 

 Lorain, Wyandot, Highland, Wayne, Fulton, Madison, Mercer, 

 Licking, Richland, Knox, Clinton, Huron, Gallon, Defiance, 

 Harrison, Fayette, Morrow, Tuscarawas, Williams. 



