iz Contributions from the Gray Herbarium 
acutis plus minusve canescentibus et hirsutis; pappo mediocriter 
copioso sordido. — Ipauo: rather dry barren slopes, Sea Foam, 
Custer Co., Aug. 5, 1916, no. 3605 (Typr, Gray Herb.). 
Hieracium Howellii Gray is nearly this species but the single 
collection by which it is known has somewhat dentate leaves with 
tawny shaggy pubescence, tomentose stems and white pappus. 
The cinereous involucre suggests H. cineritium Nels. & Macbr. but 
it has numerous heads in a close corymbose cyme. The leaves, 
too, are denticulate. 
V. A REVISION OF THE ERIGERONS OF 
THE SERIES MULTIFIDI 
By J. Francis MacpripE anp Epwin Bake Payson 
THE nomenclature of the entirely homogenous group of Erigeron 
designated by Rydberg Fl. Colo. 359 (1906), as the Multifidi has 
always been more or less troublesome. This is largely due, doubt- 
less, to the fact that mere variants have been proposed as new 
species, perhaps often because of the uncertainty of the character 
of type specimens, and by the fact that no consistent treatment 
of the group as a whole has ever been attempted. 
The greatest development of species and varieties seems to be 
attained in the central Rocky Mountains of Colorado and Wyo- 
ming although representatives are exceedingly common on alpine 
slopes and meadows throughout western North America as far 
south as northern New Mexico and southeastern California. 
Though essentially alpine (or arctic) in habitat, individuals are 
often found descending to middle elevations on gravel bars and 
exposed stony slopes in mountain regions. Members of this 
section have been collected in Greenland and Spitzbergen as well 
as in the arctic portions of North America. 
Three species are recognized and are distinguished by the 
manner in which the leaves are dissected, for this character seems 
to be fairly constant. The variation in the size of the heads, in 
the color of the rays and in the length and width of the leaf divi- 
sions, although often striking, constitute but formal differences. 
Most of the species and varieties that have been described in later 
years have been based on the presence or absence of pubescence 
