148 KaklM. Wiegand and Arthur J. Eames 



Farwell (Bui. Torr. Bot. Club 42:247. 1915) is undoubtedly right in applying 

 the name P. biflorum (Walt.) Ell. to the comiiiutatum group. His division of that 

 group into two species, however, can scarcely be accepted. After an investigation 

 of the filaments on plants from all over the range, it appears that they may be 

 either smooth or papillose, but that this character is not correlated with the variations 

 in leaf outline. The differences in color of the flowers cited by Farwell is not 

 apparent. Unfortunately it would seem, therefore, that the name P. biflorum must 

 be adopted for the whole commutatum group. Two forms of P. biflorum, as thus 

 understood, occur in the Cayuga flora: one is a plant of upland wooded banks, with 

 elliptic or elliptic-lanceolate leaves; the other grows in rich alluvial soils, and is very 

 coarse and erect, with broader, more veiny, leaves, more inclined to the stem; but no 

 constant structural characters separate these two forms. The soil requirements of 

 P. biflorum are not yet fully understood. 



16. Medeola (Gronov.) L. 

 1. M. virginiana L. Indian Cucumber Root. 

 Damp sandy or gravelly humus, and light acid soils ; common. June. 

 General throughout the basin, in gravelly soils. 

 N. B. to Minn., southw. to Fla. and Tenn. ; frequent on the Coastal Plain. 



17. Trillium L. 

 a. Stigmas short, stout, tapering from the base to the apex, recurved at the tip, about 

 half as long as the sharply 6-angled or winged ovary. 

 b. Ovary white or nearly so ; peduncles recurved or reflexed under the leaves ; 

 petals moderately or strongly spreading, color white, cream, or pinkish ; anthers 

 equaling or slightly shorter than the stigmas; plants of bottom lands; flowers 

 May 15-June 20, not ill-scented. 

 c. Anthers 2.5-6.5 mm. long, one-third longer than the filaments or less, pinkish ; 

 petals 5-17 mm. bruad, 15-26 mm. long; peduncles 0.8-4 cm. long, recurved 

 or reflexed; leaves usually slightly contracted into an obscurely petioled base. 



1. T. cemwum, 



var. tnacranthum 

 c. Anthers 6-15 mm. long, twice as long as the filament or more, yellowish white; 

 petals 10-34 mm. broad, 20-50 mm. long; peduncles 3-12 cm. long, straight, 

 horizontal, or slightly reflexed ; leaves usually not at all petioled. 



[T. dcclinatum | 

 b. Ovary dark purple ; peduncles erect or spreading ; petals spreading above, brown- 

 ish purple or greenish yellow ; anthers equaling or slightly exceeding the 

 stigmas; leaves strictly sessile; plants of hillsides, with longer leaves in pro- 

 portion to the height than in the two last-named species ; flowers Apr. 20-May, 

 ill-scented. 2. T. erectum 



a. Stigmas slender and of uniform diameter, erect or spreading, usually more than 

 half as long as the sharply or obtusely angled ovary. 

 b. Leaves sessile ; ovary sharply 6-angled ; anthers exceeding the stigmas ; petals 

 obovate, white, turning pink with age ; fruit subglobose. 3. T. grandiflorum 

 h. Leaves short-petioled ; ovary obscurely 3-lobed ; anthers equaling or shorter 

 than the stigmas; petals elliptic-lanceolate, white with purple base; fruit short- 

 oblong. 4. T. undulatum 



1. T. cernuum L., var. macranthum Eames & Wiegand. (See Rhodora 25:191. 

 1923.) 



Low, mucky, mostly acid, soils in calcareous regions; rare. May 20-June 15. 



Low island in swamp, McLean Bogs (D.\). A considerable colony exists here, 

 but the plant has not been found elsewhere in this flora. 



Vt. to Ont. and Mackenzie, southw. to Pa., 111., and Sask, 



