171 
of this ong-standing error naturally excited my interest in this 
whole group of Zrvilium, and a study of the different species 
leads me to print the following key and specific descriptions which, 
I Hope, will lead to a better understanding of these interesting 
plants. 
As far as I can see, this group of 7/iium has always been very 
unfairly treated; most authors seem to have taken it for granted 
that the number of species. was very limited and that that number 
could not be naturally increased. If an author did put his con- 
victions in print, described a new species, pointed out excellent 
characters for a species and distributed specimens, that species was 
almost certain to find itself in synonymy or reduced to varieta, 
rank of another species at an early date. This state of affairs 
continued and reached a climax in Dr. Watson’s treatment of the 
group in his revision of the North American Liliaceae,* where 
only two forms are given specific rank, while the rest are included 
in the synonymy or varietal ranks under a much distorted nomen- 
lature, for example, Z7ri/iium viride Beck appears as a synonym 
of Trillium sessile L., Trillium discolor Wray appears asa variety of 
Trillium sessile under the new name Wrayi, Trillium viridescens 
Nutt. (7: viride Beck) also appears as a variety of the Linnaean 
species under the new name Nuétallii and Trillium lanceolatum 
Boykin mss. is set down as a variety of Zrillium recurvatum, which 
is fortunate enough to have retained specific standing. 
Key to the Species, 
Petals sessile, of one color throughout. 
Sepals oblong or oblong lanceolate; petals broadly spatulate. 
1. 7. discolor. 
Sepals lanceolate ; petals lanceolate, elliptic or oblanceolate. 
Leaves oval or suborbicular, 4-8 cm. long; anthers 3-4 times longer than the 
filaments ; styles elongated, nearly straight. 2. T. sessile, 
Leaves ovate-lanceolate to ovate-orbicular, 8-18 cm. long; anthers subses- 
sile; styles almost wanting, stigmas recurved. * T. Underwoodii. 
‘Petals clawed, the blade and claw often of different colors. 
Leaves sessile; blades of the petals linear or linear-oblong. * 
- Stems anal pubescent at least above; leaves ovate or oblong ; sepals 26-5 ou 
cm. long; filaments—1-} shorter than the anthers. 4. 7: viride. 
Stems smooth; leaves lanceolate or elliptic; sepals 2-2.5 cm. long; fila- i 
ments about as long as the anthers. Se 7. lanceelatan, oe 
ves of the bene or ae 
on agen poner ‘tic Su ~ aete a 
