158 PITTONIA. 
olate to oblong-linear, the largest 3 inches long or more, all 
thinnish, deep-green, sparingly pubescent only along the 
3 veins and their ramifieations, mucronately pointed at the 
obtuse apex, the margins evenly and rather coa rsely dentate: 
involucres at the ends of all the branches, very large (3 
inch broad), campanulate, the excessively numerous bracts 
closely imbricated by their white basal part, the long linear- 
subulate green and pruinose tips widely spreading: rays 
large and numerous, deep-purple: achenes narrowly ob- 
lanceolate, closely striate, very glabrous; pappus in a single 
series, but unequal. 
Collected in the Sierra Madre, Chihuahua, Mexico, in 
Soldiers’ Cafion, 11 Oct., 1899, by Messrs. Townsend and 
Barber. A very beautiful species, related to M. Bigelovit, 
but very distinct as to character of pubescence, indentation 
of leaves, etc. 
" ALISMA BREVIPES. Perennial, the corm-like subterranean 
base of the stem fibrous-coated by the remains of last year's 
petioles; scape and panicle 10 to 18 inches high: leaves 2 
inches long more or less, of uncommonly firm texture, 
elliptic-lanceolate, or the very lowest lanceolate with sub- 
cordate base, all tapering acutely to a short and blunt some- 
what callous apex, 5-nerved, the margin also raised and 
nerve-like but thin-edged and more or less distinctly erose- 
denticulate under a strong lens; petioles very short, scarcely 
as long as the blades: naked part of the scape little if at all 
surpassing the leaves, the panicle pyramidal, ample but not 
diffuse: deltoid-ovate sepals strongly 7-nerved: petals obo- 
vate, exceeding the sepals, forming a corolla of } inch in 
breadth or more. 
In low wet places at Piedra, southern Colorado, 12 July, 
1899,C.F. Baker. Quite distinct from all other Alisma forms 
by its short petioles and peduncles, firm white-nerved and 
white-margined foliage, ete. The specimens are barely well 
in flower, no fruit having arrived at maturity. 
