88 
This species has a wide range of variation in the division and toothing 
of its leaves, but the variations are so inconstant that it seems impos- 
sible to found specific distinctions upon them. In characterizing T. 
aureum, Nuttall has laid some stress upon “lateral divisions of the upper 
leaves subsessile,” a character which means nothing, as these divisions 
may be sessile, subsesidle, or petioled upon the same plant, either in 2'. 
aureum ov the T. irifoUaium of Gray, So far as foliage characters are con- 
cerned, serrate leaflets point to Nuttall’s form, while crenately-toothed 
leaflets stand for Gray’s T. frifoUatum, exclusive of his A*ars. apterum and 
atropurpureum. Further confusion in leaf characters has arisen by in- 
cluding the so-called apterous varieties, which we have restored to 
Zizia. An extreme variation in leaf characters, but merging completely 
into the type through intermediate forms, is 
Var. trifoliatum C. & R. Bot. Gazette, xii. 136, in which 
the leaves or leaflets are crenate or crenately-toothed. — 7\ tr'ifolia- 
tum Gray, Manual, in part. 
Ohio to Illinois, westward to Oregon and British Columbia (Macoun). 
This seems to be the common western form of the species, as our 
Paciflo coast specimens are all distinctly this variety. From Ohio to Illi- 
nois there is an interminable intermingling of species and variety, Mdiile 
in Pennsylvania the specific form is distinctly represented. 
V Var. involucratum. Radical leaves twice to thrice ternate; 
leaflets as in the species: umbel with conspicuous involucre of ser- 
rate bracts, and involucels of numerous toothed bractlets often as 
long as the pedicels, which arc 2 to 8 lines long. 
Mountain meadows, Kootenai county, Idaho, July, 1887 (J. B. Leiberg). 
Var. atropurpureum C. & R. Bot. Gazette, xii. 186. Petals 
dark-purple. — 7\ atropurpuretcm Nutt. 7\ trifoliatum^ var. atro- 
purpuretim Gray, Manual. 
Same range as the species. 
This variety has the leaf cliaracters of the species, and if var. trifolia- 
tum had been retained as a species, var. atropurpureum w'ould have been 
transferred to T. aureum. 
In giving the range of the above group of forms it has been impos- 
sible to use published ranges, owing to the great confusion as to what 
forms were intended. Discarding the apterous varieties, the true Thas- 
piums of this^ group are but scantily represented in our herbaria, far more 
so, probably, than their occurence would justify. The early spring and 
summer flowers and fruits of the apterous forms have probably too often 
satisfied collectors that they had already secured good material of forms 
which only appeared in collecting condition in late summer and autumn. 
Therefore we can only cite such range as our material indicates, confident 
