Botany of Illinois and Missouri. 179 
sessile or on very short petioles. Flower closely sessile. 
Leafets of the calyx an inch long, lanceolate, acute, recurv- 
ed. Petals purple, of the length of the calyx, lance-ovate, 
very acute, attenuate at base, erect. #ilaments very short. 
oe In similar situations with the last. Apri 
may be Trillium sessile of Linnzeus; but its flowers 
differ cpieetibly from that apeniey as described in botanical 
works and as figured in Curti At all events ‘ sesszle,’ is 
now no Sai a distinctive idleictin and should be changed. 
{n. addition to the above sessile flowered species of this genus, 
it is probable 1 that at least two more have already been dis- 
covered. 
* Trillium ag ae a Me 
Var. album Pur sh. 
Rocky banks of creeks ee into, ihe Ilinois— 
common. — 
Trillium grandiflorum Salisb. 
Has. On the prairies of Illinois. May. 
In the spring of 1822, I observed this plant in flower, at 
intervals, from St.Louis to,\Cleaveland onthe Ohio, and. also 
in the western part of this Sta 
Rumex acetosella Lin. 
Has. Prairies—common. April. 
Rumex britannicus Pursh. 
Has. Swampy grounds near St. Louis. April. 
HEXANDRIA. POLYGYNIA. 
Alisma plantago Lin 
Has. Swamps 5 miles hs of St. Lsais, and clsewtere. 
HEPTANDRIA. MONOGYNIA. 
ZEsculus glabra Willd. 
Hp. On the banks of the Illinois and elsewhere. be 
