110 Rhodora [Juny 
THE FORMS OF OSMORHIZA LONGISTYLIS. 
S. F. BLAKE. 
WHILE collecting a few years ago at Cabin John, Montgomery 
County, Maryland, I became interested in the variation shown by 
the abundant specimens of sweet cicely (Osmorhiza) growing on a 
shady bank. In addition to Osmorhiza claytoni (Michx.) Clarke, at 
once recognizable by its short erect subulate styles and stylopodia, 
three other readily distinguishable forms occurred in about equal 
numbers, all with the long slender styles and stylopodia of O. longi- 
stylis (Torr.) DC. One of these was at once separable from all the 
other forms occurring by its perfectly glabrous stem. In the second 
the stem was densely puberulent with short spreading hairs about 
half a millimeter long, while in the third the stem was densely and 
canescently villous. Subsequent study has shown that the first 
of these forms, the one with glabrous stem, represents the typical 
Osmorhiza longistylis (Torr.) DC., which was described by Torrey' 
The third was described by 
“ 9 
as with “stem . . . very smooth.’ 
Professor Fernald some years ago as Osmorhiza longistylis var. villi- 
caulis, with a range from Pennsylvania to Illinois and Kansas. The 
second form has never received a name. 
The distinctive characters and ranges of these three variations of 
Osmorhiza longistylis, as shown by material in the National Herbarium, 
may be briefly stated as follows: 
1. OsMORHIZA LONGISTYLIS (Torr.) DC. Prodr. 4: 232. 1830 (typical 
form). 
Myrrhis longistylis Torr. Fl. N. & M. U.S. 1: 310. 1824. 
Uraspermum aristatum ĝ longistyle Kuntze, Rev. Gen. Pl. 1: 270. 
1891. 
Washingtonia longistylis Britton in Britton & Brown, Ill. Fl. 2: 
530. 1897. 
Stem glabrous, or slightly pubescent at the nodes. 
Tyre LocaLIiTY: New York. 
DisrRiBUTION: “Eastern Quebec to Assiniboia, south to North 
Carolina, Alabama, Kansas and Colorado." Common in the District 
of Columbia. 
2. OSMORHIZA LONGISTYLIS var. brachycoma Blake, var. nov. 
Stem, petioles, and at least the lower part of branches densely 
puberulent with spreading hairs 0.3 to 0.8 (averaging 0.5) mm. long. 
! Fl. N. & Mid. U. 8. 1: 310. 1824. 
