Davis: THALICTRUMS OF NORTH AMERICA. 511 



C. Akenes at least twice as long as broad. 



D. Plant glaucous throughout; akenes narrowly elliptical, 



tapering at base or stalked. 

 E. Divisions of leaves large, crenations broad and shallow. 



peltatmn. 

 EE. Divisions of leaves small, with small ovate teeth. 



Jaliscanum. 

 DD. Plant not at all glaucous; akenes subsessile, one side 



straight Cuernavaccmum. 



CC. Akenes a little longer than broad. 



D. Leaves once or twice ternate; leaflets large, orbicular. 



Pringlei, 

 DD. Leaves 4 or 5 times ternate; leaflets small, ovate. 



Guatemalense. 



BB. Leaflets subpeltate on only part of the plant .pubigerum. 



BBB. Leaflets not peltate nor subpeltate. 

 C. Flowers perfect. 



D . Plant pubescent longistylum. 



DD. Plant glabrous Pachucense. 



CC. Flowers monoecious or polygamous ( T. papillosum 



doubtful). 



D. Plant glabrous or only glandular, very little or no pubes- 

 cence. 

 E. Akenes ribbed, not gibbous. 



F. Leaves 45 times ternate ; leaflets i to 2 inches across. 



grandiflorum, 

 FF. Leaves 2-3 times pinnate; leaflets small and thin. 



Galeottii. 

 EE. Akenes with convex protuberances on the ribs. 



F. Anthers mucronate Hernandezii. 



FF. Anthers linear, but rather blunt .gibbosum. 



DD. Plant pubescent, hispid or hairy. 

 E. Fruits not woolly. 



F. Leaflets glabrous above, glandular-hispid beneath. 



lanatum. 



FF. Leaflets papillose above; hairy veins prominent be- 

 neath papillosum. 



EE. Fruits woolly tomentettum. 



CCC. Flowers dioacious. 



D. Leaves pinnately compound .pinnatum. 



DD. Leaves ternately compound. 



E. Styles wanting Madrense. 



EE. Styles filiform, 3-4 lines long .grandifolium. 



