XXVII. A SYNONYMIC CONSPECTUS OF THE NA- 
TIVE AND GARDEN THALICTRUMS OF 
NORTH AMERICA. 
Ks, €.. Davis. 
The name Zhalictrum (Linn. Sp. Pl. 545. 1753) is prob- 
ably from TZhallo, to grow green, and has reference to the 
young shoots which are of such a bright green color. 
This group includes several forms which are well suited for 
the mixed border and rock garden, and the robust forms are 
well placed in the wild garden. Many are very hardy, and 
only the more southern forms of those given below are at all 
tender. TZhalictrums are valued for their healthy heads of 
flowers, contrasted with their handsome stems and leaves which 
are often of a purple cast. They may be propagated by seed 
or by division of roots in early spring just as growth begins. 
Any good loamy soil will suit them if well drained. 
The latest monograph of the genus was in 1885, by LeCoyer, 
in Bull. Soc. Roy. de Bot. de Belge, where he describes 69 
species. In 1886 Wm. Trelease published a fine treatment of 
‘¢ North American species of Zhalictrum” in Proc. Bost. Soc. 
Nat. Hist. 23: 293-304, in which he recognized eleven species 
and four varieties north of Mexico. His treatment is rather 
closely followed by Robinson in Gray’s Synop. Fl. 1895. Since 
that time at least ten new species have been described—chiefly 
from Mexico—several of which are by J. N. Rose in Contr. U. 
S. Natl. Herb. 5: 185, October 31,1899. Only five have been 
introduced to our gardens from other countries. 
Erect perennial herbs: leaves ternately compound and de- 
compound; stem leaves alternate: flowers dicecious, polyg- 
amous, or perfect in some species, rather small, generally 
greenish-white or sometimes purple or yellow, borne in a 
panicle or loose raceme; sepals 4 or 5, deciduous; petals want- 
ing; stamens many, showy; carpels usually few, 1-seeded. 
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